TaskHub: Move code to be more conform with other singletons

Make methods static and add a instance() method for Signals/Slots.

Remove ProjectExplorerPlugin::taskHub() method and use the new
ones instead.

Change-Id: Ifae24ff19579fc524cbd61bddc826095c443adfa
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
fix warning C4267

We assing a DWORD to wParam when posting WM_DESTROY,
thus we can be sure that there's no loss of data.

Change-Id: I21c9b658ff06ea7792d0a357ff508bdab04fa5f7
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
RemoteLinux: Make environment reader check for exit code from env.

A non-existing command may not always result in a "FailedToStart" error,
but can also lead to "normal" finish with a non-zero exit code (from the
shell), which means that people whose remote system is missing the "env"
command currently get no feedback at all when pressing the "Fetch"
button. (Independent of this, the exit code should always be checked
anyway.)

Change-Id: I1387897436825c18e7df2d03d5ee3870ff6b70f5
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
QmlDesigner: Remove unused attention from FormEditor

Change-Id: I9cb2b9f4bffe1c80cfaf6894c934d0eece74dbda
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
QmlDesigner: Use different transform for QmlAnchorBindingProxy

Change-Id: I54bad5ddc239e3d8e91ff4f39c74bab780c658f2
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>