Escape special characters in *_shell.bat.

Windows uses ^ for escaping since \ is taken as the path separator.

The characters are in the commented-out value of the MSYS variable. If
the command were uncommented, cmd.exe would complain about syntax
errors.
msys2-unlocker: Still very WIP
libffi: Update to 3.2.1
mercurial: Update ot 3.2.1
msys2-runtime: update to git SHA [fbf8a84]
ruby: Update to 2.1.5
crosstool-ng: Generate checksums
get_terminal_width checks both STDIN and STDOUT
Merge pull request #122 from jbutera/master

get_terminal_width checks both STDIN and STDOUT
conemu: new package
pacman: Removed fix for upstream bug that is now fixed
Merge pull request #125 from elieux/pacman-fs42736-fixed

pacman: Removed fix for upstream bug that is now fixed
filesystem: Added MSYSTEM to the default prompt
Merge pull request #126 from elieux/prompt-msystem

filesystem: Added MSYSTEM to the default prompt
filesystem: Fixed PKGBUILD (broken in previous commit)
Merge pull request #127 from elieux/prompt-msystem-v2

filesystem: Fixed PKGBUILD (broken in previous commit)
pacman: Update to git SHA [6889f48]
msys2-runtime: Update to git SHA [8211578]
groff: Update to 1.22.3
msys2-unlocker: Started splash screen (WIP)

Turning this into a bit of a do-it-all thing, may make
it like busybox, so the behaviour depends on argv[0].