Do not assume that the complete message fits into tht buffer when sending in VariableSizeCommunicator

Closes #105

See merge request !416

If the buffer is small the we need to issue multiple sends and receive.
Unfortunately, the logic when sending was broken before this commit. It
simply always assumed that the buffer was larger than the complete message
to be send.

Feature/add cmake flags to dunecontrol

Closes #93

See merge request !378

It is now possible to pass -D...=... flags to CMake via configure-opts.
Bash- / Autotools-style variables like CC=.. or MPICC=.. are no longer
support in configure-opts.

Autotools are history, no need to check for libraries built by libtool.

[Doc] Reverse-engineer variablesizecommunicationtest

See merge request !415

Add editor hints to variablesizecommunitationtest.cc

See merge request !414

That test is a bit difficult to understand unless you know what it tries to
do, which is a problem if that is exactly what you're trying to figure out.
Here are my notes from trying that.

It seems to have magically escaped The Great Reindent, and of course uses
indent depth 4, not 2.

[dune_add_test] Do not check existance of EXPECT_COMPILE_FAIL targets.

Closes #100

See merge request !413

Fixes: #100.  See also: !404.

Those targets never exist -- instead, cmake is invoked during testing to
attempt to build them.

Revert "Merge branch 'fix/dune-add-test-cmake-guard-skip-test' into 'master'"

See merge request !406

This reverts merge request !405

[cmake][dune_add_test] Set test property to depend on existence of target

Closes #100

See merge request !404

[cmake][dune_add_test] Fix cmake guard and skipping tests

See merge request !405

If a complicated user defined command was specified, it didn't lead to the dummy
executable (that return 77) being run but the user defined command instead. This
patch makes sure that the correct command is executed which then marks the test
as skipped and not as failed.

If the target was not found in the current state the test fails. With this
patch the ctest states "Not Run" and the name of the missing target.

fix disableCopyMove for empty arguments

See merge request !383

add fallback implementation of `is_invocable` and `is_invocable_r`

See merge request !393

Remove Pardiso from script am2cmake.py

See merge request !397

Pardiso isn't supported anymore by dune-istl.

[test] check whether default-constructed forward iterators compare equal

See merge request !350

Fixed usage of std::abs in fmatrixtest.cc to allow ADL

See merge request !391

The implementations simply forward to the current implementation of
`is_callable`. See #83 for more details.

[Sphinx] Support special cmake_params.

See merge request !390

These are parameters that cannot be easily fit into the other categories.  For
instance a family of single-value parameters:

  [NAME1 value1 [NAME2 value2 ...]]

You can pass the exact string to appear in the synopsis via :argname:.

This also allows to work around a with multi-valued positional
parameters (a.k.a. ARGV-like parameters).

quotient must be representable without error

See merge request !387

The quotient must be representable exactly for the division test to
work on i386 as `1./3. == 1./3.` can be false when using the FPU due
to store/load cycles.

[cmake] Update UseLATEX.cmake to upstream 2.4.6

See merge request !380

Removed a trailing white space

add changelogs from release to master

See merge request !385

fix several typos

See merge request !386