massive restructure, and updated api documentation

* moved testsuite out of main package
* converted core modules (readers, networks, etc.) to packages, and
split methods into modules
Merge branch 'erick' into python

Conflicts:
	doc/api_doc/.doctrees/environment.pickle
	doc/api_doc/.doctrees/index.doctree
	doc/api_doc/.doctrees/tethne.doctree
	doc/api_doc/.doctrees/tethne.testsuite.doctree
	doc/api_doc/_modules/index.html
	doc/api_doc/_sources/index.txt
	doc/api_doc/_sources/tethne.testsuite.txt
	doc/api_doc/genindex.html
	doc/api_doc/index.html
	doc/api_doc/objects.inv
	doc/api_doc/py-modindex.html
	doc/api_doc/searchindex.js
	doc/api_doc/tethne.html
	doc/api_doc/tethne.testsuite.html