This reverts commit 4441ec26.
The minimal required is finally GCC 4.7 or newer (it is actuall 4.9).
Original commit message for d26e5ed3 was
    [C++11] Follow the C++11 specification of operator new.

    The signature changed in C++11 which we require now.
    To get more details see the mailinglost in October 2012.

Thanks to Marian for the heads-up and the testing.

Use ALLOW_CXXFLAGS_OVERWRITE instead.

Drop support for std=c++0x.

They were tested until 2.3 and are now always supported due to
the new compiler requirements.
Removed macros: HAVE_INTEGRAL_CONSTANT, HAVE_DUNE_HASH,
HAVE_STD_HASH, HAVE_TYPE_TRAITS, HAVE_VARIADIC_TEMPLATES,
HAVE_VARIADIC_CONSTRUCTOR_SFINAE, HAVE_RVALUE_REFERENCES

Otherwise FieldVector<K,1> is not literal and its size()
method can never be used as constexpr.

This makes the code more robust and (a bit) more robust.  Additionally,
it repairs the recent breakage that I introduced by modifying promotiontraits.hh.

Otherwise FieldVector is not a literal type and
calling its size() method is not a const-expression
although size() itself is declared as constexpr.

The previous implementation consisted of a list of promotion rules for
various types.  The new implementation is much shorter and more general:
it will also work for types not on the old list.  The promoted type is
now defined as the result type of the addition of the two input types.
There is no special reason to use addition here, but it does reproduce
the precise behavior of the old implementation.

The 'macroname' variable is still used by the code, but its definition
was accidentally removed together with the AutoTools-generating code.
Therefore, duneproject would fail with

/home/sander/dune/dune-common/bin/duneproject: Zeile 695: dune-foo/cmake/modules/: Ist ein Verzeichnis

This patch puts the missing definition back in.

Document an incompatibility issue of index_sequence
and add a reminder to fix this as soon as we allow
template aliases.
This can only be fixed

This does not apply cleanly to the release.

by testing whether we work on a end iterator. In this case the distance
function will fail. Found that out by gcc's stdlib with debugging turned on.

When using NO_DEFAULT_PATH the lib and include subdirectories will
not be searched by default by find_path and pt-scotch will not be
found outside of the standard path. This commit adds them and now
locally installed versions may supersede the system ones.

Without it linking will fail when using static libraries due
to missing symbols.

These are the *.la files below dune and the primary module library
lib<module name without dashes>.la.

This reverts commit 21dbaefe.
Thus if libtool libs are found, then we abort again.
Please do not merge to the release.

Since commit 495f2fce USE_MPI was removed from dunecontrol and
the default configuration now defaults to use
parallelism. Unfortunately, there are downstream modules that try to
support multiple versions of DUNE. Sometimes these need to decide
whether to support parallelism before they know which version of DUNE
they are using. This is was not possible when providing
--enable-parallel as no variable gets set for DUNE>=2.4.

With this commit dunecontrol always sets
CMAKE_DISABLE_FIND_PACKAGE_MPI to an appropriate value. Thus if
dunecontrol is used then one can check in one's own module whether the
variable is set explicitly to false and conclude that one is using
>=2.4 and wants parallelism. Otherwise one can check USE_MPI to detect
which behaviour is needed for 2.3.

E.g. like this:
<code>
option (USE_MPI "Use Message Passing Interface for parallel computing" OFF)

if( NOT CMAKE_DISABLE_FIND_PACKAGE_MPI STREQUAL ""
    AND NOT CMAKE_DISABLE_FIND_PACKAGE_MPI)
  set(USE_MPI ON)
endif()

if (NOT USE_MPI)
      set (CMAKE_DISABLE_FIND_PACKAGE_MPI TRUE)
 set (CMAKE_DISABLE_FIND_PACKAGE_MPI TRUE)
endif (NOT USE_MPI)
</code>

Of course without dunecontrol and using the defaults one will still
configure DUNE as parallel, but one's own module as sequential.

Actually, having these files lying around does not hurt us.
In addition there are downstream modules that especially create
these for compatibility reasons with autotools. For these
reconfiguring a module using dunecontrol currently aborts with an error

Therefore this commit resorts to just issuing a warning and proceeding
with the compilation instead of aborting with an error.

... and don't take absolute value of comparison result.
Thanks to Max Kahnt for reporting this.

The add_doxygen_target macro now takes optional parameters:
TARGET [name] : overwrite the target appendix, default is the module name
DEPENDS [list] : add a list of further dependencies for doxygen.
                               This list might include mainpage.txt
OUTPUT [name] : change the name of the output target; necessary if you don't generate html.

Otherwise it won't appear in the doxygen documentation

We follow the advice of upstream and use only empty endif() and
else() statements in new code. The removal of the optional argument
is only in generated scripts.

Add missing files, remove ancient buildsystem stuff and stuff where it is
unclear where it comes from.