Code Cleanup:
- Change HashMap to Map in local variable declarations
- Extract checking of the trial instance is not a delete environment to isEnvironmentNotDeleted()
- join if conditions
- extract updating of MeasurementVariable during loading of measurement table to processMeasurementVariable
- added checking for deleting an environment in loadDataMeasurement()
- extract the checking if a measurement variable is a trial instance to isATrialInstanceMeasurementVariable
- yung isEmpty() for checing if the collection is empty
- remove useless parenthesis()
- use double quotes for element attribute in html

BMS-85

Reviewer: Mae Isabelle Turiana