CMake: add install targets for Linux and Windows

* add install target for Windows
* add install target for Linux
* use executable path instead of current dir (fix troubles when falltergeist was launched not from its folder)
* add support for Linux bin/lib/share scheme

Also, with this pull request it is possible to make packages with falltergeist.

ppa: https://launchpad.net/~pavlyshko/+archive/ubuntu/falltergeist