[TYPO3-core] RFC #11684: Add support for flash messages in the backend

[Ingo Renner]

Hi all,

the attached version of the patch has been committed to trunk r5816.

- the unnecessary UPDATE queries have been prevented
- @author tags have been removed in t3lib_FlashMessage
- to actually add the messages to modules it's now possible to use a 
dedicated marker ###FLASHMESSAGES### if present, otherwise they're 
forced to be displayed before the rest of the module's content
- renderFlashMessages() has been changed to public instead of protected

For the ExtJs part that has been requested by Xavier, Rupert, and 
Steffen: As I'm not familiar with ExtJs and its best practices I kindly 
ask you to contribute a solution to access the flash messages. I think 
that'd be in the best interest of everybody, at least I don't see a lot 
of sense in me creating a solution that either doesn't work or doesn't 
comply to best practices. It'd also be of little help having me to try 
to make it work over a lot of iterations and wasting time while some of 
you may simply do it in a fraction of the time I would need to do that.

Also I'd rather have the features in before feature freeze and then add 
little improvements later on instead of not having the features at all. 
I hope you can agree with that.


API documentation will follow until the end of the week.


all the best
Ingo

-- 
Ingo Renner
TYPO3 Core Developer, Release Manager TYPO3 4.2