Added support for Auto- and SelfLoader-loaded code

Core modules AutoLoader and SelfLoader support delayed compilation by
allowing Perl code that follows __END__ and __DATA__ tokens,
respectively.  When we detect that one of these modules is used in the
file, we continue processing even after we see the corresponding token
that would usually terminate parsing of the file.
Tests for {Self,Auto}Loader support in perl.c
Merge pull request #87 from dtikhonov/master

Support for Auto- and SelfLoader-loaded code (with tests!)

TODO: converting all Tests/*.pl to Units/.