implemented RedisContainer

also TestCase now sets up a test database
added Redis database support to Wall

added title and posted attributes to Post
added static cls attribute to PostHandler
implemented Wall.get_history and Wall.get_history_msg
implemented Wall.post_msg
added Redis database index to default.cfg
added Redis dependencies to README
implemented DoPostHistoryHandler

added icon for DoPostHistoryHandler
added ui to DoPostHandler constructor
Merge branch 'generic-brick' into history
Merge remote-tracking branch 'origin/master' into history

Conflicts:
	wall/__init__.py
	wall/bricks/url/__init__.py
	wall/res/static/wall.js
Merge pull request #52 from NoyaInRain/history

History implemented