When using CHAR(N) in PostgreSQL any inserted value smaller than N
characters will be right-padded with spaces to fill all N characters.
See: https://www.postgresql.org/docs/9.1/static/datatype-character.html

This change adds an additional Mode.padFixedStrings and set it to true
in the PostgreSQL Mode. Any value converted to a ValueStringFixed at
INSERT will be right-padded with spaces.

For additional infos see the H2 Google Groups post:
https://groups.google.com/forum/#!topic/h2-database/Luaxdrl137Y

use a set to keep track of the tables we need to analyze.
Perform the analysis after we have committed the main transaction, so we
don't hold table locks for any longer than necessary.

* Custom data types handler

* Updated doc, changelog, dictionary. Fixed review comment.

* Extended the custom types handler interface

* Fixed test

* Fixed review comments

* Added note on ABI stability of the feature to docs

Currently the JDBC type of TIMESTAMP WITH TIME ZONE is Types.OTHER.
JDBC 4.2 has a dedicated type for this Types.TIMESTAMP_WITH_TIMEZONE.

Unfortunately this type is only available in JDBC 4.2/Java 1.8 so I
hard code the constant value instead of the constant reference.

Some PRs merged into 1.4.193 and 1.4.194 are missing from the
changelog.

* 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