Accept float sexagesimal minutes when seconds are missing
add support for 'dm' and 'hm' formats with float minute values
Addressing PR comments, remove asarrays
Changing s default to None
Fix test
Modifying documentation
Adding CHANGES entry
Add more Angle test to test_angles.py
Merge pull request #2846 from bsipocz/coordinates_accept_more_formats

Angle accepts hours:mins or deg:mins initializers (without seconds) and float minutes for these cases