Simplified atomicity analysis: now PBNonTerminals know whether they are atomic.
or not.
Now the atomicity analysis only needs the LCA to determine the atomicity of a
word instance.  This also fixes a subtle bug where a word instance is reported
as atomic but can in fact be executed non-atomically.
We can now analyze word instances on LCA, avoiding building the whole tree up
to the root.
Fix timer bug when the parser throws a ParserAbortedException.
Timer bug when the grammar is empty.
Profiling vars could overflow with 32bit integers.  We now use long (64bit).
Improved AnalysisMain handling of the atomicity analysis.
Minor changes in isLoop().
Merge branch 'atomicity-rework'.