Add FAQ file
Install documentation files
Merge pull request #145 from rworkman/docs

Add FAQ and install docs during make install
Add new FAQ file to changelog
Optionally add Thunar sendto and Xfce settings support

This also renames --enable-sendto to --enable-nautilus-sendto
to clarify that the option enables nautilus-sendto, as there
is also a thunar-sendto option now.