Fixed whitespace
Added auto-insertion of @memberof tags

functions of the form Foo:bar now get @memberof Foo prepended to the
output.
Added support for multi-line comments

Multiline comment blocks of the form --[[! ... ]] are included in
documentation.
Correct handling of multiline block comment close

Both the forms '--]]' and ']]' are now handled correctly.
Previously only the former worked.
Comments preserved inside code blocks

This only affect code blocks specified with @code/@endcode.
Code blocks can also be specified in a markdown-fashion, via indentation.
To deal with this case would complicate the script quite a bit, however.
Added automatic @ingroup directives for non-local functions

For a function of the form foo.bar.baz(...) the directive @ingroup foo
is prepended to the function declaration. No check is made as to whether
the group actually exist, but if it does not the directive is a no-op.

This only handles a single level of grouping.