Get rid of redundancy, add sanity check, better status reporting.

Task-number: QTCREATORBUG-1460

Reviewed-by: kh1

Reviewed-by: Kai Koehne

QTCREATORBUG-1661

Task-number: QTCREATORBUG-1770
(cherry picked from commit 4dffc2aa)

 * Fix "instantiated from" with leading spaces being wrongly considered
   an error.
 * Add a unit test to cover this case

(cherry-picked from 503b3534)

(cherry picked from commit b87f3fbc)

 * Should work better with errors that can happen during deployment
(cherry picked from commit 3d2e5667)

 * Gcc 4.5 reports fatal errors. Parse them correctly.
(cherry picked from commit 1d887410)

(cherry picked from commit ef55312c)

this is rather theoretical, but anyway ...

Should have been part of 5b47f47d

Task-number: QTCREATORBUG-1649
Reviewed-by: ck

Task-number: QTCREATORBUG-1859

This time by porting to the ApplicationOutputwindow

cherry-pick of fd01cc976aff8da1efe55bc8ad9eeb05a04f08e1

Enabling other plugins to know which tasks currently exist.

Fixes the performance of large find scope selections. Try
Ctrl+A Ctrl+F in a large file and scroll.

See Qt Merge-request: 727, change a9c8decc741d8c2b340f38d7a854ef206672ab3e,
which makes wchar_t a native type. QString::toUtf16() no longer is
a WCHAR.

Users can still go to plugin manager and manually enable the plugin.

Reviewed-by: con

Task-number: QTCREATORBUG-1765
Reviewed-by: ck

StringBuilder problems ...

image providers to supply pixmaps so that the Image::source property can be
used instead.

Reviewed-by: kkoehne

Reviewed-by: Christian Kamm
(cherry picked from commit 3281a9e6)

Reviewed-by: con

The remote terminal likes to insert backspaces just for fun.

Note to the merge person: This commit might trigger a merge conflict.
In that case, just use the code from the master branch.

Disable the spinboxes once we disable packaging.

Reviewed-by: ck

Previously it would always jump to the start of the document, since
that's where the newly created text cursor is at the beginEditBlock
call. Avoid this when saving the current editor by starting with the
cursor of the editor.

Reviewed-by: mae
Task-number: QTCREATORBUG-1807

As a custom icon is set in most cases anyway.

Reviewed-by: Robert Loehning <robert.loehning@nokia.com>

If we where not in full help mode at least once, the engine
would still run without valid help collection due to the new
lazy initialisation, thus the right side pane would not be
able to retrieve the requested help file.

Reviewed-by: ck

(cherry picked from commit 7ccf903ee3d9da4a104310ed423130857d59d91b)