Clarify return type of number_type(); fixes #18
Add Python 3 note to readme
Merge metadata updates from upstream r578
Generated Python files for metadata
Merge metadata updates from upstream r579
Generated Python files for metadata
Merge code changes from upstream r579
Prep for 5.6 release
Merge branch 'dev' into python3

Conflicts:
	python/phonenumbers/data/alt_format_49.py
	python/phonenumbers/data/region_BG.py
	python/phonenumbers/data/region_CD.py
	python/phonenumbers/data/region_DE.py
	python/phonenumbers/data/region_IN.py
	python/phonenumbers/data/region_MY.py
	python/phonenumbers/data/region_PT.py