prepare release

all tests pass
added test for complement set
Merge pull request #9 from antlr/prepare-release-4.5

prepare release
added visitor code
Merge pull request #10 from antlr/replicate-python-2-visitor-code

added visitor code
add edit warnings
Merge pull request #11 from antlr/add-warnings-in-generated-tests

add edit warnings
Missing reference
add support for $self
moved from $self to $parser

also adjusted generated tests for the above and moved back to member
tokens
Merge pull request #12 from antlr/add-$parser-support

Add $parser support
Fixed encoding bug