As we have bumped our compiler requirements to GCC 4.4+, we can now
require the compiler to support C++11.

This patch updates both the autotools and the CMake tests to produce an
error if the compiler doesn't support either -std=c++11 or -std=c++0x.

It also renames the tests from ..0X to ..11 and renames the configure
options from --disable-gxx0xcheck to --disable-cxx11check and removes a
couple of redundant calls to the autotools macro.

Deprecate header and macro dune_static_assert.
Use static_assert instead.

They cased compiler warnings.

Avoid upper case commands.

They do not find a package but check for a feature.
This avoids false warnings about not found packages.
Merged FindCXX11Conditional.cmake and FindCXX11Features.cmake.

The test result was never used. The test slipped in as a copy from
the CMake code snippet from DuMuX.

r7472.

[[Imported from SVN: r7473]]

templates.

This way dune-common compiles as before if variadic templates _and_
move semantics are not present.

[[Imported from SVN: r7454]]

[[Imported from SVN: r7450]]

[[Imported from SVN: r7073]]

[[Imported from SVN: r6773]]

[[Imported from SVN: r6741]]

directly into the various CXX_FLAGS.
This prevents warnings.

[[Imported from SVN: r6651]]

[[Imported from SVN: r6640]]

Do not use cmakedefine01, as DUNE relies on the fact that there is no
define if a feature is not there.
Use a similar order for the defines in config.h.cmake for better
comparsin with e.g. meld.

[[Imported from SVN: r6594]]

[CMake] Added test for C++11 features.

[[Imported from SVN: r6578]]