Build pre-built compilers for 5.7.1.

Revert the change to PolyThreadMaxStackSize. This is actually a "full…

…" call.

Version 5.5.2. fixes-5.5.2 was branched from here.

Version 5.5.1. fixes-5.5.1 was branched from here.

Version 5.5. fixes-5.5 was branched from here.

Version 5.4. fixes-5.4 was branched at this point

5.3 Release - 5.3.fixes was branched here

5.2 Release. This is approximate.

5.1 Release.

Version 5.0 Release