Range.color property is introduced

Range.color property is introduced
Allows to assign color to the given
range with RGB color codes (255, 0,0) or RGB constants 'rgbRed'
Returns RGB color code.
Range.hyperlink property and Range.add_hyperlink method are introduced

Allows to assign hyperlinks to the given cell range with text2display
and screen_tip arguments.
Merge branch 'master' of https://github.com/kvdogan/xlwings into kvdogan-master
refactored hyperlink
more refactoring of Range.hyperlink and added tests
made hyperlink tests cross platform compatible
refactored Range.color
implemented Range.color on Mac and addded tests
Merge branch 'kvdogan-master' into develop