working on doc tickets
starting rewrite of install docs
Adding docs about installing in develop mode.
interim ci
modified release docs.
adding new url for downloads
adding source build to travis-ci
Merge pull request #268 from pastephens/docs

updating travis file
Merge pull request #269 from darribas/issue226

Adding towsp method in W
updating release docs
Merge pull request #270 from sjsrey/doc_sr

updating release docs
- example and doctests for spatial gini
Merge pull request #275 from sjsrey/spatial_gini

Example and doctests for spatial gini
- updating api docs
Merge pull request #276 from sjsrey/spatial_gini

- updating api docs
update when added
Merge pull request #277 from sjsrey/spatial_gini

single line update to txt, not waiting for travis
- adding diagonal option to kernel weights in user.py
Merge pull request #285 from sjsrey/diag

- adding diagonal option to kernel weights in user.py
- having build_lattice_shapefile also create the associated dbf file
- useful for testing our contiguity builders against geoda since dbf is
  required by the latter