CppEditor: Fix moving definitions

* Move initializer lists completely
* Respect whitespace as it is

Task-number: QTCREATORBUG-9462
Task-number: QTCREATORBUG-9463

Change-Id: Id9c41394b4aa55b0a85957286ab42f2ce8966c08
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>
CppTools: Open InsertionPointLocator::methodDefinition for symbols

Remove restricted use of declarations and add an option to define if
SymbolFinder should be used to find a matching definition for symbol.

Change-Id: If5cf5b11926e116766dd60dd3726b4fcf2e1c9f5
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>