MySQL for Python MySQLdb-SVN

Added joinTM.py which inherits from the standard ZRDB.TM and overrides its
_register() method to use the transaction's join() method directly. This avoids
a couple unnecessary abstraction levels and avoids some problems with the
overridden _register() and the transaction's register(). The former has a bare
except: that hides useful errors. The latter deals poorly with exceptions
raised from the join due to state modifications made before the join attempt.

This raises the Zope Dependency to Zope-2.8 or newer.

Changed the variables() method to be simpler and not hide errors.

Change a text exception to a class based one.

Removed reference to old _tlock attribute in _begin()'s except block.
Also added a comment about a redundancy.

Upping version to 3.0alpha3 for new release.

Removed usage of str.strip in map call in favor of list comprehension.
Did this to prevent issues with unicode values.

Some cleanups and extensions to the database introspection methods.

Cleanup.

Mostly added some comments and doc strings.
Removed some unused imports.
Couple formatting adjustments.

unicode_literal fixed to use MySQLdb's method

Fixing bad variable name.

Reworked unicode supporting code to use MySQLdb's unicode support.
As a plus, it now actually works in limited testing.

Also tweaked auto-create database to support creating unicode tables.

Note unicode support is still hardcoded as utf8. Though it theoretically
could be changed by subclassing/overridding the use of the DB class as it
is hardcoded as an attribute on it.

Removed the thread lock from around the pool read call as it is only necessary
around the writes.