#315 removing HDX_ROOT parameter

replacing with HDX_FOLDER
Merge pull request #316 from OCHA-DAP/configuration-change

Pull req: #315 removing HDX_ROOT parameter
#315 adding postgres jdbc library to pom.xml
Merge pull request #317 from OCHA-DAP/configuration-change

Pull request: #315 adding postgres jdbc library to pom.xml
Changing version number to 0.5.7
Merge pull request #318 from OCHA-DAP/dev

Pull request for merging dev into master for version 0.5.7