[Development] Commit policies and the Qt 5 alpha

[lars.knoll at nokia.com]

Hi everybody,

there are quite a few people meeting up in Oslo this week, and we'll try
to finish up the Qt 5 alpha there. For this reason I'd like everybody to
restrain themselves in what they submit to the master branch. The main
focus needs to be to get the alpha, so please focus on staging only
commits that help us get the alpha out.

At the same time, I'd like to announce that we need to tighten our policy
regarding changes to Qt 5 a bit more. This is required for us to really
focus on stabilizing Qt 5, and bringing us onto the right path towards a
release. 

Here are the new rules for essential modules:

* From now on no more changes that are source incompatible with Qt 4.8.
	1-2 exceptions are still waiting in the API changes branch and Thiago's
new QUrl.
* No more source incompatible changes to features/API that are new in Qt
5, unless approved by the module's maintainer after a discussion on the
mailing list
* Try to avoid binary incompatible changes, as they slow down development.
* The only changes that should still go in are:
	- Regressions against Qt 4.x (this implies that the platform plugins have
some more freedom)
	- Major bugs for functionality that has been there in 4.x	
	- Bug fixes to new functionality
	- Performance improvements
	- Improvements to memory consumption

Qt Addons are encouraged to follow the same rules if they want to have a
5.0 release at around the same time as Qt 5.0.

Cheers,
Lars