Add a -providerPath option to jarsigner

Summary

Add a -providerpath option to jarsigner so that it can load a keystore implementation not provided by JDK. keytool already have the same option long ago.

Problem

If a keystore implementation is not inside JDK, using it with jarsigner needs the -J-cp -Jpath/to/jar option. We should follow the keytool style by providing a dedicated option for it.

Solution

Add a -providerpath option to jarsigner. It works with the -providerClass option to load an external keystore implementation just like in keytool.

Specification

jarsigner -help will shown an extra line for this new option.

[-providerPath <list>]      provider classpath

Add the following lines into the "Options for jarsigner" section of the jarsigner page at https://docs.oracle.com/en/java/javase/17/docs/specs/man/jarsigner.html#options-for-jarsigner:

`-providerPath` *classpath*
:   Used to specify the classpath for providers specified by the `-providerClass`
    option. Multiple paths should be separated by the system-dependent
    path-separator character.