Bumps version to 5.7.1-2
This fixes several issues:
- Prevents a hang for user input during the build.
- Moves the tools into a subdirectory so their DLLs do not interfere with other packages.
- Adds the currently installed DLLs to the path so that tools compiled during the build can be run.
- Uses our system's copy of double-conversion.
- No longer uses looped builds; I haven't seen issues since the update to JOM 1.1.2
- Works around an issue with Qt5Bootstrap (QTBUG-55499)
Regressions to fix:
- Disables many subcomponents
