Implemented operators like +=, -=, etc for ordinals, floats and string
Programs using the UnitTest module will now report the number of failed tests as the exit code of test runs (0 for successful run)
Added: PNimrodNode.lineinfo for better error messages from macros
Added: seq.splice
For easier use from templates and macros, except stament now supports
the list of exception types to be supplied in nkBraket node (array literal).