Preview: Hibernate Search 5.0, new HQL Parser

@anistor hi, please have a look at this preview as we're finalizing HS5.

Besides the obvious changes in API/SPI with some packages moved and some classes renamed, there is a significant change in mapping: all Integer, Long, Float, Double, Date and Calendar fields are *by default* mapped to Numeric Field types. With explicit mapping you can still get the old behaviour, but this seemed to have a rather tricky effect on the assumptions we make in the HQL Parser & related code.
I have updated the Parser but didn't release it yet (still working on adding last unit tests to it), but FYI with these changes all tests seem to pass.

Changeset doesn't seem too scary now, but when I started with this I had almost 300 failures ;-)