Added nicer install script for OS X.
Fixed Linux install.sh after move to /opt.
Fixed OS X make uninstall script.
Added nicer uninstall scripts for OS X and Linux.
Updated compilation instructions after 45c4ee5.
Merge pull request #3 from Bo98/mac-install-script

Added nice OS X install script, fixed Linux install.sh, fixed make uninstall_osx, added nicer uninstall scripts (uninstall.sh) and updated compilation instructions