Added Address function to Range Object

Need to
1) determine if other parameters should be accepted (R1C1 address type
and reference cell)
2) Determine if other (more Pythonic) ways of supplying parameters
should be supported
3) Determine if Mac syntax is different and current and add
Revert "Added Address function to Range Object"

This reverts commit 88ff4d8f356899dd7b3c6067aac46a9c9423f38b.
Merge remote-tracking branch 'upstream/develop' into develop
get_address

Added a get_address method to the Range object.
Merge remote-tracking branch 'upstream/develop' into develop
updated get_address function

Shortened lines.
Fixed examples in comment.
Removed sheetname_only argument.
Added sheetname_only parameter back in
Merge remote-tracking branch 'upstream/develop' into develop

Conflicts:
	xlwings/_xlwindows.py
	xlwings/main.py
Revert "Added sheetname_only parameter back in"

This reverts commit 94adf6ef2c20065ed03df9e40e3c0664e122df8a.
Added sheetname_only parameter back in
Merge remote-tracking branch 'upstream/develop' into develop

Conflicts:
	xlwings/_xlwindows.py
	xlwings/main.py
Merged with upstream