Bugfix: pushd into SHARK_PROJ_DIR before running sbt/sbt compile in the new "skip tests" codepath.
Bugfix: pushd into SHARK_PROJ_DIR before running sbt/sbt compile in the new "skip tests" codepath.

mattyb149/blinkdb,lzshlzsh/shark,sjyk/sampleclean,mapr/shark,mattyb149/blinkdb,sjyk/sampleclean,sjyk/sampleclean,amplab/shark,mattyb149/blinkdb,amplab/shark,sameeragarwal/blinkdb,mapr/shark,lzshlzsh/shark,lzshlzsh/shark,sameeragarwal/blinkdb,amplab/shark,alabid/blinkdb,sameeragarwal/blinkdb,alabid/blinkdb,mapr/shark,alabid/blinkdb