Thanks to Tobias Malkmus for the heads-up.

The majority of developers favor individual headers for (emulation of) C++11
features over collecting them in a single header cxx11.hh. This patch
renames cxx11.hh to constexpr.hh and moves it into the subdirectory std.
This is the place most developers would like these headers in (see
http://users.dune-project.org/doodles/4).

As decided on the developer meeting in Aachen, we support (but do not
rely on) the C++11 keyword constexpr. This patch adds an m4-check for
constexpr and a header (cxx11.hh) defining a macro DUNE_CONSTEXPR either
as constexpr or empty (depending on the compiler support for it). It is
then used in FieldVector and FieldMatrix on size, rows, and cols.

[[Imported from SVN: r7379]]

[[Imported from SVN: r7124]]

Add basic support for hashing using Dune::hash

This patch introduces the functor Dune::hash in a similar manner to
other C++11 functionality by importing the definition from namespace std.

Apart from that, the patch also provides some basic functionality to simplify
making user-defined types hashable, in particular functions for combining hashes
and hashing iterator ranges as well as a mechanism for defining the struct
specializations required by std::hash and std::tr1::hash in the correct namespace.

The current implementation will first try to use std::hash and, if that fails,
attempt to fall back on std::tr1::hash. If that is not available either, hash
support is disabled as there is no homegrown fallback for now.
The extension mechanism will register the type with both std::hash and std::tr1::hash,
if available. This should make it possible to use unordered_{set,map} from both C++11
and TR1 without having to specify a custom hasher.

Kudos to Steffen Müthing, see FS#1192

[[Imported from SVN: r7065]]

Capabilities to compute eigenvalues on non-symmetric matrices
Code contributed by Arne Morten Kvarving.

[[Imported from SVN: r7061]]

[[Imported from SVN: r7042]]

There are lots of power implementations all over our code.
This is the first step of some cleanup.  It moves the class Power_m_p
from misc.hh (like who's ever gonna find it there...) to a separate
header power.hh.  Other implementations will be collected there as
well, if appropriate.

With the patch, including misc.hh will issue a cpp warning that people
who include misc.hh only for Power_m_p should now include power.hh
instead.  This is not great, because it also affects people who include
misc.hh for something else.  Bear with this for a while; I couldn't
think of a better solution.

[[Imported from SVN: r7032]]

rename files... remove underscores

[[Imported from SVN: r7012]]

[[Imported from SVN: r7009]]

[[Imported from SVN: r7006]]

[[Imported from SVN: r6999]]

It is used from the dune-geometry module (see FS 1180).

[[Imported from SVN: r6995]]

[[Imported from SVN: r6930]]

[[Imported from SVN: r6925]]

SmartPtr< T > is similar to shared_ptr< T > in its intention. However, it
demands methods addReference and removeReference on the object it points to.
Actually, you could implement shared_ptr< T > through a
SmartPtr< RefCountWrapper< T > > and a few cast operators.

[[Imported from SVN: r6919]]

[[Imported from SVN: r6902]]

[[Imported from SVN: r6886]]

- add dotproduct for basic data types
(thanks to Matthias Wohlmuth)

[[Imported from SVN: r6862]]

dune-geometry.

[[Imported from SVN: r6796]]

[[Imported from SVN: r6795]]

[[Imported from SVN: r6596]]

[[Imported from SVN: r6557]]

[[Imported from SVN: r6544]]

[[Imported from SVN: r6487]]

[[Imported from SVN: r6456]]

[[Imported from SVN: r6453]]

[[Imported from SVN: r6436]]

[[Imported from SVN: r6403]]

indices for geometry types.

[[Imported from SVN: r6390]]

This code used to be in ConfigParser, which I will deprecate in a second.
The new implementation is inspired by boost: each parser is a global method
in a namespace.  In our case, that namespace is a class ParameterTreeParser,
because it needs to have some private methods (ltrim and rtrim, to be
precise).  On demand, parsers for more formats can be added to this class/file.

I do not insist on any of the details of this new code. However, I wanted
to have the many architectural change before the creation of the 2.2 release
branch.

[[Imported from SVN: r6346]]

[[Imported from SVN: r6343]]

make documenting interfaces easier.

[[Imported from SVN: r6300]]

[[Imported from SVN: r6258]]

[[Imported from SVN: r6239]]

[[Imported from SVN: r6193]]

* factor out most of the FieldMatrix math methods

missing: several functions oculd not me moved, as they require som
		 kind of type promotion traits

[[Imported from SVN: r6181]]