Windows: Fix stepping through Qt sources.

Build paths of Qt 5.2 changed.

Task-number: QTCREATORBUG-11233
Change-Id: I9e3b2d53cb10f09bc1b9d780669ebb72c595ad4f
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
WelcomPage: Fix intitial filtering by Qt version

When having multiple Qt versions with examples registered in Creator,
the welcome mode showed all of them initially.

The reason was that m_uniqueQtId was initialized with noQtVersionsId
instead of uniqueQtVersionIdSetting().

The function uniqueQtVersionIdSetting() gets the correct Qt version from
the settings as shown in the combobox.

Task-number: QTCREATORBUG-10790

Change-Id: I9f435f6372f8b0c0495daf6c6efcf4bcc5e70455
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Fix change-of-sign warning found by ICC

-1 is not a valid unsigned value.

registerhandler.cpp(354): warning #68: integer conversion resulted in a change of sign
          return createIndex(row, col, TopLevelId);
                                       ^

Change-Id: I41935255704f19724d6cec16ea470e2f8f8a16a1
Reviewed-by: Kurt Pattyn <pattyn.kurt@gmail.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
Qnx: Add missing placeholders to labels

Change-Id: I472cacaea48495bb039b18426bbb2010673d1a65
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>