Fix CI failures, remove generated files from Git

[zbynek]

There are several problems with the CI setup this PR intends to fix:

• the CI always runs on release branch, even for pull requests. That makes it impossible to test code before merging.
• the no_local_java_generator_version kicks in, meaning that integration tests use the last released version of the generator instead of the local one that should be tested
• some tests have different results on Windows depending on the line ending. This could be possibly fixed by changing the git checkout flags, but adding fixcrlf ant task makes this more robust.
• on Windows the encoding needs to be specified so that UTF-8 encoded test grammars compile
• the .gitignore file covers *.out and *.err files, but not files called simply out and err. Fixed by renaming.
• some expected compiler outputs in tests were outdated

[new-javacc]

Thank you for this great clean up! I will let @MarcMazas take a quick look and merge.

[MarcMazas]

Looks usefull! Thanks.
I want to finish the maven plugin before, so in 1 or 2 weeks.
What about PRs #4 & #6? Still relevant?

[zbynek]

@MarcMazas I'd like to see the other PRs merged as well, but I have to resolve the conflicts first.

[MarcMazas]

Thanks. I also would appreciate you create the same PRs for the c++ & c# versions :-).
(c# is at the same level than java, c++ has full error reporting not yet implemented, and some examples & grammars not yet fully adapted - that is why some are bypassed).