Fix code in TestPerformance that clears the DFA
Fix build error
Must check rule transition follow states before eliminating states in the ATN (fixes #224)
Remove unnecessary local
Remove comments with incorrect concurrency requirements
Remove unnecessary duplicate conditions
addDFAEdge needs to return the true target state of the added edge
Don't try to optimize read-only configuration sets
Allow ATN fallback in parser to continue to use DFA edges when available
Remove unnecessary locals
Add computed state to DFA before moving to full context simulation
Add error edges to DFA
Remove execDFA - it doesn't do anything execATN doesn't do
Remove statistics that lost their meaning
add counter for stack graph nodes.
Merge pull request #226 from sharwell/parser-simplification

ParserATNSimulator simplification; removes explicit DFA or ATN with stack simulation.
Merge branch 'master' of github.com:antlr/antlr4
tweak my tests for java.
Revert "add counter for stack graph nodes."

This reverts commit 43e73c8da9d66b7c7fa0522802dcb437509d4903.
Add the SHUFFLE_FILES_AT_START and SHUFFLE_FILES_AFTER_ITERATIONS options to TestPerformance