Patch to add gnome-like copy-paste shortcuts

This patch will add an option to allow gnome-like copy past shortcuts : Ctrl-Shift-C and Ctrl-Shift-V.
When enabled, it disables the auto copy on select feature (which can be annoying) but leave the right click paste according to the "xterm mouse" setting.

The "Detect URLs on selection and launch in browser" settings has been moved to make place or this option (plus, this setting is windows only and it was in the multiplateform settings).