Revert "Bug 1039739 - Make it more clear what command we're executing;r=yuren"

This reverts commit 74caef0139574c7fcf2c77255df9088f44a4dafe.
Revert "Bug 1039739 - Add some logging when writing the git commit id into the settings app;r=yurenju"

This reverts commit 8d0f21f728c837276b2ad3484213f623622c81bf.
Revert "Bug 1036821 - git commit hash isn't wrote to settings/resources/gaia_commit.txt on Windows"

This reverts commit 6b6c77c2a1b93deab5466744bb857b37ec755567.