Start of a major refactoring to use objects.
add this new file
DFXP -> WebVTT working on a very basic level.
More refactoring
incomplete untested refactor of sami
Misc fixes, port scc.
Ported the rest of this stuff.
Fixes to SAMI support
fix webvtt timestamp output
Fix style parsing in sami reader.
Fix review comments from Drew.
Make DFXP writer output UTF-8
Fix SCC simulated roll up.
Don't return None for an empty caption set
Merged in changes from PBS master, fixed tests, added WebVTTReader and .vtt example file, updated readme, squashed bugs
Merge with PBS Master

Conflicts:
	README.rst
	pycaption/__init__.py
	pycaption/dfxp.py
	pycaption/sami.py
	pycaption/srt.py
	setup.py
	tests/test_dfxp.py
	tests/test_sami.py
	tests/test_srt.py
Merge branch 'master' of https://github.com/rdio/pycaption into rdio-master

Conflicts:
	pycaption/__init__.py
	pycaption/transcript.py