[intellij] make antlr based completion optional
Corrected typos in XbaseInterpreter

Signed-off-by: Miro Spönemann <miro.spoenemann@itemis.de>
Corrected documentation of short-circuit evaluation of Elvis operator

Signed-off-by: Miro Spönemann <miro.spoenemann@itemis.de>
added an example on how to use the intellij completion APIs

Change-Id: I615fa8b46b33ef6c055da13acc2ba4fa58bd96ae
Merge "Corrected typos in XbaseInterpreter"
Merge "[intellij] make antlr based completion optional"
Merge "added an example on how to use the intellij completion APIs"
Merge "Corrected documentation of short-circuit evaluation of Elvis operator"