ewmh.py: clean up whitespace at end of file.
README.rst: fix English
README.rst: add license information.
ewmh.py: fix a crash in getActiveWindow
ewmh.py: improve English
ewmh.py: fix spelling of UNKNOWN returned by _getAtomName
ewmh.py: fix indentation (not significant for Python!)
Merge pull request #2 from rrthomas/master

Various improvements - thanks to rrthomas