[#64349062] changes done and tested according to the comments.

Method names changed in data.py, only works for GraphCollection Objects
now.
Merge branch 'ramki_jan29' into python
[#64940190] Flask related initial files.
Cleaned up docstrings, etc
fixed GraphCollection.nodes() and .edges()
Merge branch 'python' into erick

Conflicts:
	.DS_Store
	tethne/data.py
.nodes and .edgs