Reviewed-by: kh

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

The margin on the other panels is being set to 4, while the search panel
used the default margin.

Reviewed-by: Jens Bache-Wiig

 - show side-by-side if possible
 - always show side-by-side
 - always show full help

The default is "show side-by-side if possible". It's currently considered
possible if the editor is at least 800 pixels wide.

There were both variants, with and without extra semicolon.

Task-number: 254695

Task-number: 253365

Task-number: 253365
Reviewed-by: kh

Task-number: 253365
Reviewed-by: dt

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

Also, find the help pages for Creator on the web properly.

Reviewed-By: kh

The qt_help cataloge is required to fully translate the help plugin. The
additional lookup is mandated by the binary packages, where the translations
are simply put in Creatrors translation directories and the Qt translation
path is invalid.

Reviewed-by: con <qtc-committer@nokia.com>

Reviewed-by: dt

- clear up some Q_OS_LINUX vs. Q_OS_UNIX
- clear up Q_WS_* vs. Q_OS_* (relatively theoretical exercise)
- use proper #if-#else cascades instead of free-standing #ifs

Reviewed-by: dt

Reviewed-by: dt

Reviewed-by: dt

Reviewed-by: Daniel Molkentin

Reviewed-by: Daniel Molkentin

When an example is selected, help and the project are opened
in a split view. We try to read the xml file provided for
QtDemo to extract details about the examples provided. Will
try all available Qts, starting with the default version. Will
fail gracefully (provide a message and disable controls) if
examples or demos cannot be found. Will work if help is not
found, but show an error.