resource(".xls") -> Excel

adds into(DataFrame, Excel) using pd.read_excel
Merge branch 'master' into resource_excel

Refactor resource(Excel) for new regex technique
add into(DataFrame, Excel) tests in test_into.py

Conflicts:
	blaze/api/into.py
	blaze/api/resource.py
	blaze/api/tests/test_resource.py
	blaze/data/__init__.py
Adding Coveralls
Added blank line
Added setup.cfg file for arguments.
Added new coverage method to .travis.yaml.
Removed setup.cfg/ trying out pytest-cov.
Merge branch 'master' into resource_excel

Conflicts:
	blaze/api/tests/test_into.py
Removed --cov from command line arguments. Apparently the plugin
automaticaly adds itself, and I get an error when I run it with the
command line module.
Merge pull request #539 from talumbau/resource_excel

resource(".xls") -> Excel
Update README.md
Testing travis build.
Using coverage, which coveralls may like better.
Push for rebuilding.
Silly syntax mistake!
add datashape to sparksql type converter
spark: discover on pyspark rdds
resource on chunks passed kwargs

cc @chdoig
spark: into sparksql <- spark
resource on chunks passed kwargs

cc @chdoig