Update Spark requirements
Update TODO.md
Update README to use install_github
Merge pull request #4 from shivaram/master

Update README to use install_github
Use one style ($) for accessing names in environments.
Merge pull request #6 from concretevitamin/env-style-fix

Use one style ($) for accessing names in environments.
Add Travis CI integration (using craigcitro/r-travis)
Merge pull request #7 from JoshRosen/travis

Add Travis CI configuration
Move dev install directory to front of libPaths
Merge pull request #8 from shivaram/master

Move dev install directory to front of libPaths
Use smaller broadcast and plyr instead of Matrix
Matrix package takes around 2s to load and slows down unit tests.
Merge branch 'master' of github.com:amplab/SparkR-pkg into unit-tests
Update travis to install plyr
Merge pull request #10 from shivaram/unit-tests

Make unit tests a bit more faster
Search rLibDir in worker before libPaths
This ensures we pick up the SparkR intended and not an older version
installed on the same machine
Merge pull request #11 from shivaram/master

Search rLibDir in worker before libPaths