Windows: Create response files for too long commands when .bat files are exported

[NiklasRosenstein]

With the ninja:speed=1 option, the Ninja backend exports batch files rather than using the Build Server and Client to improve build performance.

This mode does not incorporate response files yet, resulting in too long commands being written into batch files, ultimately failing the build. Interestingly, batch seems to randomly drop characters if a line is too long, instead of giving a warning or error.