Refactored serverGetRequest as hidden function in globalEnv
Added Hal syntax parser

This simplifies the returned HAL syntax, removing the embedded layers
Cleaned up and clarified devCommands statements
Refactored controller logic of connection functions
Cleaned devCommands and adapted it to previous commit
getObservations now also uses HAL response from tranSMART
Merge branch 'feature/addHalParsing' into transmartRClient