Prepend brew-cask dirs to $LOAD_PATH (not append)

Found while investigating #2275, but probably not a fix, just a sensible
change. Depending on version of ruby interpreter, previous code could
cause brew-cask paths to came later than current dir "." in $LOAD_PATH,
leading to unpredictable behavior in the wild.
add milkytracker
Android Studio 0.4.1 build 133.967590
Add cask for LÖVE
Merge pull request #2361 from selesse/android-studio

Android Studio 0.4.1 build 133.967590
Merge pull request #2363 from andrewschleifer/love

Add cask for LÖVE
node-webkit 0.8.4
Merge pull request #2365 from ndr-qef/node-webkit

node-webkit 0.8.4
Merge pull request #2341 from rolandwalker/prepend_load_path

Prepend brew-cask dirs to $LOAD_PATH (not append)
moved league of legends to Casks dir
Merge pull request #2366 from vitorgalvao/correct-league-of-legends

moved league of legends to Casks dir
Merge pull request #2367 from yyolk/milkytracker

Cask for Milkytracker
Android Studio 0.4.2 build 133.970939
Merge pull request #2368 from selesse/android-studio

Android Studio 0.4.2 build 133.970939
added new cask tongbu