Change-Id: I8b73d583be1ee7183f4074bce49d5390e38631a2

Reviewed-by: hjk

Task-number: QTCREATORBUG-3141

Reviewed-by: Tobias Hunger

Do not fail when cloning non-defautl branches from local repositories:
Branches do already exist in this case, so do not try to set them up
again.

Handle detached HEADs as well as cloning from repositories that default
to another branch but master. This is relevant when clonig local
repositories.

Reviewed-by: Friedemann Kleint

Change the mapping of repository name to checkout directory name.
This should now work better with windows.

 * Polish the base checkout wizard
    * Make UI easier to grasp
    * Add tooltips explaining things

Task-number: QTCREATORBUG-2540
Reviewed-by: Robert Loehning

Fix commiting with Author and Email set on Windows.

Task-number: QTCREATOR-2397

... for git, hg as it is not obvious from the SHA1 displayed.

Provide UI with manual refresh button in BaseCheckoutWizardPage.
Change ProcessCheckoutJob to be able to execute several steps.
Implement in git.

Do not clobber environment setting for SSH_ASKPASS.
Pass on QProcessEnvironment to CheckoutWizard.

- Use message boxes on timeouts.
- Add a configuration for a graphical SSH password prompt binary with
defaults
- Launch commands that require authentification with no terminal on UNIX
and environment variable SSH_ASKPASS set accordingly.
- First attempt at introduce a common function to synchronously run VCS
commands in base plugin with flags.
- Use standard execution log entries in all VCS plugins (outputwindow).

... based on the git clone wizard. Provide a wizard for browsing
gitorious hosts.

Task-number:  44831

Task-number: 244831