Update README.md

Merged build and usage as both seem to be the same thing just two ways to get there as most Github users have Git.

Note: Linux GTK Client was listed as a Key Socket server. Neither really mean anything for users and are implementation details. Renamed to daemon to mean that it's just a program running in background (no matter client or server).
Update README.md

Inform about load unsafe script issue.
Merge pull request #56 from wernight/master

Updated readme for bug #55