Add helper function to execute a bash script
rename data loader
Add build sql cmd helper function
throw exception when gphost etc are not set. A bit of refactoring
use java.io.File.delete() instead of rm in dataloader, add load for postgres
Add test for \copy
Add gpload -- needs testing
comment out gpload tests -- needs testing
update test.sh to include gpfdist settings -- needs testing
remove trailing ; for \copy
try copy with wildcard
update loader wildcard test
fix loader function
update gpload
merge master
fix schema tests
fix data unload copy order
Merge pull request #142 from HazyResearch/loader_and_helpers

New loader/unloader code, move some helper functions to a separate file, add and fix tests.
Merge branch 'master' into develop

This merge is for incorporating the changes from Feiran's and Sen's loader_and_helpers branch.
It also brings develop and master to the same point, so that we can start fresh using a sensible development model.