As a part of the ongoing process of cleaning up and improving our handling of warnings, the time has now come to the solstudio compiler.

Just as we have done with gcc (-Wall -Wextra), we should increase the general warning levels on solstudio, and then -- if needed -- disable individual warnings. Warnings should be disabled on a per-library level if they indicate real issues that should be fixed, or globally if they are deemed not relevant for the project as a whole.

(Unfortunately, for solstudio, some warnings that really should be fixed applied to just about every library, and for sanity's sake I had to disable them globally.)