DOC: Fix formula import convention.
DOC: Fix broken link
Merge pull request #1514 from jseabold/fix-formula-import

DOC: Fix formula import convention.
Merge pull request #1515 from jseabold/fix-docs-link

DOC: Fix broken link
DOC: Be clear about data attribute of Datasets
Merge pull request #1517 from jseabold/datasets-docs

DOC: Be clear about data attribute of Datasets
DOC: Update examples contributing docs for current practice.
Merge pull request #1516 from jseabold/uploading-examples

DOC: Update examples contributing docs for current practice.
DOC: Ask for release notes and example.
Merge pull request #1518 from jseabold/contributing-docs

DOC: Ask for release notes and example.
ENH: Miniconda-based testing on Travis-CI

Experimental branch that uses miniconda rather than platform
python to test.  Has some advantages in that it is simple to reconfigure
alternative combinations of NumPy, SciPy, Cython and pandas easily,
at least as long as they are provided by Anaconda.