Bash-Support: Better support for custom mapleaders.

- Added 'Bash_SetMapLeader' and 'Bash_ResetMapLeader'.
C-Support: Documentation.

- Documentation: setting of compiler and linker flags
- Documentation: system-wide installation
Git-Support: Set path of all executables at once.

- Added 'g:Git_BinPath' to set the path for all executables at once.
Matlab-Support: Support for custom mapleaders.

- Added 'Matlab_SetMapLeader' and 'Matlab_ResetMapLeader'.
- Fixed setting and resetting of maplocalleader in filetype plug-ins.
- Improved the release script.
- Documentation.
- Minor changes.
Merge remote-tracking branch 'upstream/master'