Re-implement IBM doublebyte charsets to boost the coding perfomrance and reduce the storage footprint.

We are seeing
(1)20% size reduce of the charsets.jar
(2)much faster coding performance

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Diff <x-IBM930> <x-IBM930_Old>...
    Encoding TimeRatio x-IBM930_Old/x-IBM930: 1199,480 :2.497917
    Decoding TimeRatio x-IBM930_Old/x-IBM930: 888,620 :1.432258
    Encoding(dir) TimeRatio x-IBM930_Old/x-IBM930: 3457,2173 :1.590888
    Decoding(dir) TimeRatio x-IBM930_Old/x-IBM930: 3059,2632 :1.162234
-----------------------------------
Diff <x-IBM933> <x-IBM933_Old>...
    Encoding TimeRatio x-IBM933_Old/x-IBM933: 2991,453 :6.602649
    Decoding TimeRatio x-IBM933_Old/x-IBM933: 838,575 :1.457391
    Encoding(dir) TimeRatio x-IBM933_Old/x-IBM933: 4704,1573 :2.990464
    Decoding(dir) TimeRatio x-IBM933_Old/x-IBM933: 1971,1681 :1.172516
-----------------------------------
Diff <x-IBM935> <x-IBM935_Old>...
    Encoding TimeRatio x-IBM935_Old/x-IBM935: 896,369 :2.428184
    Decoding TimeRatio x-IBM935_Old/x-IBM935: 714,502 :1.422311
    Encoding(dir) TimeRatio x-IBM935_Old/x-IBM935: 1817,1361 :1.335048
    Decoding(dir) TimeRatio x-IBM935_Old/x-IBM935: 1590,1453 :1.094288
-----------------------------------
Diff <x-IBM937> <x-IBM937-Old>...
    Encoding TimeRatio x-IBM937-Old/x-IBM937: 1941,1056 :1.838068
    Decoding TimeRatio x-IBM937-Old/x-IBM937: 1800,1132 :1.590106
    Encoding(dir) TimeRatio x-IBM937-Old/x-IBM937: 4124,2873 :1.435433
    Decoding(dir) TimeRatio x-IBM937-Old/x-IBM937: 3686,3092 :1.192109
-----------------------------------
Diff <x-IBM939> <x-IBM939_Old>...
    Encoding TimeRatio x-IBM939_Old/x-IBM939: 1180,469 :2.515991
    Decoding TimeRatio x-IBM939_Old/x-IBM939: 875,627 :1.395534
    Encoding(dir) TimeRatio x-IBM939_Old/x-IBM939: 2313,1691 :1.367830
    Decoding(dir) TimeRatio x-IBM939_Old/x-IBM939: 2092,1828 :1.144420
-----------------------------------
Diff <x-IBM942> <x-IBM942-Old>...
    Encoding TimeRatio x-IBM942-Old/x-IBM942: 908,525 :1.729524
    Decoding TimeRatio x-IBM942-Old/x-IBM942: 659,480 :1.372917
    Encoding(dir) TimeRatio x-IBM942-Old/x-IBM942: 2511,1673 :1.500897
    Decoding(dir) TimeRatio x-IBM942-Old/x-IBM942: 2545,1792 :1.420201
-----------------------------------
Diff <x-IBM943> <x-IBM943-Old>...
    Encoding TimeRatio x-IBM943-Old/x-IBM943: 1047,516 :2.029070
    Decoding TimeRatio x-IBM943-Old/x-IBM943: 666,485 :1.373196
    Encoding(dir) TimeRatio x-IBM943-Old/x-IBM943: 1748,1336 :1.308383
    Decoding(dir) TimeRatio x-IBM943-Old/x-IBM943: 1618,1416 :1.142655
-----------------------------------
Diff <x-IBM948> <x-IBM948-Old>...
    Encoding TimeRatio x-IBM948-Old/x-IBM948: 2022,1193 :1.694887
    Decoding TimeRatio x-IBM948-Old/x-IBM948: 1431,1040 :1.375962
    Encoding(dir) TimeRatio x-IBM948-Old/x-IBM948: 3823,2971 :1.286772
    Decoding(dir) TimeRatio x-IBM948-Old/x-IBM948: 3485,2965 :1.175379
-----------------------------------
Diff <x-IBM949> <x-IBM949-Old>...
    Encoding TimeRatio x-IBM949-Old/x-IBM949: 2570,530 :4.849057
    Decoding TimeRatio x-IBM949-Old/x-IBM949: 707,527 :1.341556
    Encoding(dir) TimeRatio x-IBM949-Old/x-IBM949: 4263,1535 :2.777199
    Decoding(dir) TimeRatio x-IBM949-Old/x-IBM949: 1734,1526 :1.136304
-----------------------------------
Diff <x-IBM950> <x-IBM950-Old>...
    Encoding TimeRatio x-IBM950-Old/x-IBM950: 2025,973 :2.081192
    Decoding TimeRatio x-IBM950-Old/x-IBM950: 1432,1045 :1.370335
    Encoding(dir) TimeRatio x-IBM950-Old/x-IBM950: 3799,2992 :1.269719
    Decoding(dir) TimeRatio x-IBM950-Old/x-IBM950: 3578,2996 :1.194259
-----------------------------------
Diff <x-IBM970> <x-IBM970-Old>...
    Encoding TimeRatio x-IBM970-Old/x-IBM970: 2257,394 :5.728426
    Decoding TimeRatio x-IBM970-Old/x-IBM970: 537,442 :1.214932
    Encoding(dir) TimeRatio x-IBM970-Old/x-IBM970: 3771,1222 :3.085925
    Decoding(dir) TimeRatio x-IBM970-Old/x-IBM970: 2025,1464 :1.383197
-----------------------------------
Diff <x-IBM942C> <x-IBM942C_OLD>...
    Encoding TimeRatio x-IBM942C_OLD/x-IBM942C: 871,460 :1.893478
    Decoding TimeRatio x-IBM942C_OLD/x-IBM942C: 690,491 :1.405295
    Encoding(dir) TimeRatio x-IBM942C_OLD/x-IBM942C: 1773,1383 :1.281996
    Decoding(dir) TimeRatio x-IBM942C_OLD/x-IBM942C: 1624,1397 :1.162491
-----------------------------------
Diff <x-IBM943C> <x-IBM943C_OLD>...
    Encoding TimeRatio x-IBM943C_OLD/x-IBM943C: 965,477 :2.023061
    Decoding TimeRatio x-IBM943C_OLD/x-IBM943C: 660,482 :1.369295
    Encoding(dir) TimeRatio x-IBM943C_OLD/x-IBM943C: 1752,1382 :1.267728
    Decoding(dir) TimeRatio x-IBM943C_OLD/x-IBM943C: 1667,1410 :1.182270
-----------------------------------
Diff <x-IBM949C> <x-IBM949C_OLD>...
    Encoding TimeRatio x-IBM949C_OLD/x-IBM949C: 2569,496 :5.179435
    Decoding TimeRatio x-IBM949C_OLD/x-IBM949C: 719,516 :1.393411
    Encoding(dir) TimeRatio x-IBM949C_OLD/x-IBM949C: 3337,1518 :2.198287
    Decoding(dir) TimeRatio x-IBM949C_OLD/x-IBM949C: 1734,1556 :1.114396
-----------------------------------
Diff <x-IBM1381> <x-IBM1381-Old>...
    Encoding TimeRatio x-IBM1381-Old/x-IBM1381: 976,442 :2.208145
    Decoding TimeRatio x-IBM1381-Old/x-IBM1381: 722,488 :1.479508
    Encoding(dir) TimeRatio x-IBM1381-Old/x-IBM1381: 1763,1396 :1.262894
    Decoding(dir) TimeRatio x-IBM1381-Old/x-IBM1381: 1608,1396 :1.151862
-----------------------------------
Diff <x-IBM1383> <x-IBM1383-Old>...
    Encoding TimeRatio x-IBM1383-Old/x-IBM1383: 908,398 :2.281407
    Decoding TimeRatio x-IBM1383-Old/x-IBM1383: 555,466 :1.190987
    Encoding(dir) TimeRatio x-IBM1383-Old/x-IBM1383: 1673,1324 :1.263595
    Decoding(dir) TimeRatio x-IBM1383-Old/x-IBM1383: 1438,1398 :1.028612