JBIDE-18004: Renamed command handler
Unsetting value in combo only if it does not exist
Upgraded to Forge 2.8.2-SNAPSHOT
JBIDE-18004: Allowing pre-populated parameter values
Upgraded Aesh runtime
JBIDE-18179: Using ShellHandle refactoring
JBIDE-18179: Updating height accordingly. Need fix on width
JBIDE-18173: Remove 'Add Forge Runtime feature for Forge 1.x'
JBIDE-18179: Terminal size is now correctly calculated. 

Thanks goes to Alexey Kazakov for providing the code to calculate the
font extend.
Removed unused code
Using constant for Package Explorer