* Added parsing of table hints

* Implemented USE INDEX hints

* Added docs, tidied up code for submission

* Added docs, tidied up code for submission

* Removed used of final static field that would cause problems with Tomcat class unloading

* Removed used of final static field that would cause problems with Tomcat class unloading

* A table with no index hints now has indexHints == null, instead of an employ instance of IndexHints. For the common case of no index hints, this will prevent some unnecessary object creation.

* Index Hints now is backward compatible with using the "USE" as a table alias

* Added TestIndexHints to list of all tests

* Added index hints to text generated by TableFilter.getPlanSQL();

* Improved field names (a field called indexList was actually a set);
Added test for ensuring getPlanSQL lists index hints in correct order

* Improved unit test for making sure getPlanSQL renders index hints list in correct order

Fix multi-threaded mode insert exception "Unique index or primary key violation", test case by Anatolii K

Added new BITGET function, that returns true if and only if a specified bit in a long is set. This helps simulate bit fields in H2, which is an approach I'm using to significantly shrink database size.

reported by Alexander (vraimax2016)

since it breaks all the tests.

this reverts commit 37641c9a

Fix bug in picking the right index for INSERT..ON DUPLICATE KEY UPDATE when there are both UNIQUE and PRIMARY KEY constraints.

It's already implemented and working:
https://github.com/h2database/h2database/pull/150

(a) on modern platforms, it's way faster to call this
(b) its more accurate
(c) on my SSD, queries are fast enough the System.currentTimeMillis does
not provide a decent measurement