QString: Use QChar/char where appropriate, do not use QString::null

Reviewed-by: ck

foreach()-Loops.

QString: Use QChar where appropriate.

Reviewed-by: ck

 - if there is no LastQtVersionUpdate we doesn't have a real timestamp and we are not able to check against this.
 - this will happen during/after installation with qt bundled versions

 Reviewed-by: Daniel Molkentin

 - if there is no LastQtVersionUpdate we doesn't have a real timestamp and we are not able to check against this.
 - this will happen during/after NDK installation

 Reviewed-by: Daniel Molkentin

This assumes that new Qt version entries will be put into
the System scope settings file.

Instead note that it is invalid if trying to build and on the projects
mode pane.

Task-Nr: QTCREATORBUG-459

Reviewed-by: thorbjorn

  * Use id() for methods returning a string used to represent
    some type of object.
  * Use displayName() for strings that are meant to be user
    visible.
  * Quieten some warnings while touching the files anyway.
  * Move Factories to their products in the plugins where that
    was not done before.

Reviewed-by: dt

The only part that is not done if not on Windows (or explicitly
specified) is the adding of the preference pane.

Task-number: QTCREATORBUG-463
Reviewed-by: dt

Works now.

Reviewed-By: Thorbjorn

no point in re-parsing them over and over during the scan of a bigger
project ...

shaves off another 20% of the loading time of Qt 4.6.

there is no point in throwing away and re-recreating invariant data over
and over ...

shaves off ~15% of the load time of Qt 4.6.

Should fix a lot of corner cases, might introduce a few bugs.
Also rename functions/slots to be better named.

Generic Project Manager and CMake Project Manager are missing from this
patch.

Reviewed-by: Tobias Hunger <qt-info@nokia.com>

 * Export QTDIR and path to Qt binaries with native
   directory separators.

Reviewed-By: con

 * Handle SBSv2 by doing the same as for the older ABLD
   build system.

Reviewed-By: con

Factor out the initialization setting up the environment and headers in
the RVCT/GCCE toolchains.
Modify the RunControl to be able to support different package
building/signing processes.

Reviewed-by: Robert Loehning

Reviewed-by: dt <qtc-committer@nokia.com>

Instead simply pass -mkspec default, which has the same effect.
Fixes a bug with qws mkspecs