Editors: Move id() from editor to document.

Change-Id: Ib81076842ab1c16832224790194b001206404d64
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Update README

We require OS X 10.7 and Visual Studio 2010 now.
We only support building with clang on OS X.
The private headers section only applies to Qt 4 builds.

Change-Id: I3c566c6d7a81592f65a2ed6bae9c7185a9d7a3b8
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
UserFileVersionHandler: Api clean up, rename functions

Also rename class from UserFileVersionHandler to VersionUpgrader
userFileVersion -> version
displayUserFileVersion -> backupExtension
update -> upgrade

Change-Id: I2641b6eaee13aa07380a3ccf0e4c13d61f18f920
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
SettingsAccessor: Refactor helper functions for merge/track sticky

Instead of a template use a abstract base class.

Change-Id: I92675bf1c19ef60bec22836eda56240c2f2e4c80
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
Rename Version$Handler to UserFileVersion$Upgrader

That name is cleaner.

Change-Id: Idafc6d01b79f1748884a77fe06d407a76fa83026
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>