- Unexport Core::Internal::MainWindow and remove its includes.
- Move RssFetcher from Core::Internal to Core.
- Unexport CopyTaskHandler.
- Move TextEditor's completion support and Refactor Overlay
  helper classes from TextEditor::Internal to TextEditor as they
  are exported.
- Move internal BaseTextBlockSelection into private header.
- Unexport TextEditorOverlay as they are not used.

Reviewed-By: con

QML examples are now read like any other Qt example, but still get their
own dropdown box.

Advantages:   Less code, proper naming, also loads the help if available
Disadvantage: Only contains a few examples, instead of all. We now
              trust whoever made the selection for Qt Demo.

Reviewed-by: con

- Move RSSFetcher to CorePlugin
- Rename RSSFetcher to RssFetcher
- Make RssFetcher more generic, allow multiple sources to be fetched
- Introduce Featured Items on Getting Started page
- Introduce dummy entry for Mobile examples, needs implementation once they are ready

Reviewed-by: dt

Reviewed-By: Jens Bache-Wiig

Done with Danimo. Most changes are cosmetic but we modified
the tutorial listing and re-arranged some of the layouts to
better reflect the suggestions by Ergosign and Nigel.

Looks more structured now.

Fixes creating these pages unnecessarily when the Welcome plugin is not
loaded, as well as "leaking" them in that case.

Reviewed-by: con

This removes the all hard dependencies to and from welcome screen,
except the one to the core plugin. More in detail:

- Add IWelcomePage to add a tab to the welcome screen
- Move tabs in the modules where they belong
- Enables QHelpManager to open help fullscreen and contextually
- "Getting Started" moves to Qt4ProjectManager
- Projects & Sessions (aka "Develop") moves to ProjectExplorer
- "Community" remains in the welcome plugin for simplicity

Reviewed-by: Trust Me

Conflicts:

	src/libs/cplusplus/CppBindings.cpp
	src/libs/cplusplus/CppBindings.h
	src/libs/cplusplus/FastPreprocessor.cpp
	src/libs/cplusplus/FastPreprocessor.h
	src/plugins/cpptools/cppcurrentdocumentfilter.cpp
	src/plugins/cpptools/cppcurrentdocumentfilter.h
	src/plugins/cpptools/cppsemanticsearch.cpp
	src/plugins/cpptools/cppsemanticsearch.h
	src/plugins/duieditor/parser/qmljs.g
	src/plugins/duieditor/parser/qmljsast.cpp
	src/plugins/duieditor/parser/qmljsast_p.h
	src/plugins/duieditor/parser/qmljsastfwd_p.h
	src/plugins/duieditor/parser/qmljsastvisitor.cpp
	src/plugins/duieditor/parser/qmljsastvisitor_p.h
	src/plugins/duieditor/parser/qmljsengine_p.cpp
	src/plugins/duieditor/parser/qmljsengine_p.h
	src/plugins/duieditor/parser/qmljsgrammar.cpp
	src/plugins/duieditor/parser/qmljsgrammar_p.h
	src/plugins/duieditor/parser/qmljslexer.cpp
	src/plugins/duieditor/parser/qmljslexer_p.h
	src/plugins/duieditor/parser/qmljsmemorypool_p.h
	src/plugins/duieditor/parser/qmljsnodepool_p.h
	src/plugins/duieditor/parser/qmljsparser.cpp
	src/plugins/duieditor/parser/qmljsparser_p.h
	src/plugins/duieditor/parser/qmljsprettypretty.cpp
	src/plugins/duieditor/parser/qmljsprettypretty_p.h
	src/plugins/duieditor/rewriter/rewriter.cpp
	src/plugins/duieditor/rewriter/rewriter_p.h
	src/plugins/duieditor/rewriter/textwriter.cpp
	src/plugins/duieditor/rewriter/textwriter_p.h
	src/shared/cplusplus/ASTClone.cpp
	tests/manual/cplusplus/main.cpp

Reviewed-by: Trust Me

I don't want it in the run configurations.

Note: as for qt projects, this is also used for running. And we don't
use it for running cmake yet.

Makes it possible to reuse that code, which I intend to do for cmake and
running.