Check for playbin gstreamer element at runtime

(cherry picked from commit 0af825f5f3865cd8550d112e8361aada3a4def25)
Release version 0.10.3

(cherry picked from commit 61df3fa7dc7c3d107975f125fb60ccc8426e08f9)

Conflicts:
	README.md
	configure.ac
Update installation instructions for Fedora
Update RPM .spec file