See https://reuse.software/ for a description.

The new code uses Dune::IsNumber to end the recursive counting.
Incidentally, this removes one more of the few uses of the
'blocklevel' mechanism.  It also removes one level of indirection
within the implementation.

This addresses the following error when using GCC 8:

```
/usr/include/c++/8/bits/stl_tree.h:457:21: error: static assertion failed: comparison object must be invocable as const
       static_assert(is_invocable_v<const _Compare&, const _Key&, const _Key&>,
```

we have to preceed the variadic parameter by T1, in order to fix the deduction. The problem is
that (for what ever reason) otherwise the type pack can not be detected properly.

The code still uses boost::fusion, though.

Rene Milk authored 11 years ago and Markus Blatt committed 11 years ago

This is part of the patch provided by Rene in Flyspray 1355.

Because it does not currently have any measurable benefits.

[[Imported from SVN: r1769]]

[[Imported from SVN: r1758]]

Improved it such that placement new is only called when necessary.

[[Imported from SVN: r1757]]

[[Imported from SVN: r1713]]

Patch by Uli Sack

[[Imported from SVN: r1639]]

Patch by Uli Sack

[[Imported from SVN: r1638]]

and ScaledIdMatrix

Patch by Uli Sack

[[Imported from SVN: r1637]]

[[Imported from SVN: r1635]]

[[Imported from SVN: r1482]]

[[Imported from SVN: r1341]]

[[Imported from SVN: r1305]]

Fixed some more bugs.
Patch was provided by Atgeirr Rasmussen.

[[Imported from SVN: r1143]]

* update configure and Makefiles

[[Imported from SVN: r1100]]

Made parallel SOR work with amg.

[[Imported from SVN: r1079]]

Parallel AMG works on helics with repartitioning!

matrixredistribute.hh : Ensure that overlap rows have the right entries
matrixutils.hh : Added method to print a distributed sparse matrix
amg.hh: initialize pointer with zero to prevent deallocation of nonallocated storage.
hierarchy.hh: print operator complexity in verbose mode.
transfer.hh: removed wrong assertions (yes, Index sets can have holes!)
repartition.hh: Bugfix: Use the correct MPI datatype to unpack. (Unpacking a std::size_t using MPI_INT on 64 bit is not a good idea!)

[[Imported from SVN: r1076]]

[[Imported from SVN: r904]]

[[Imported from SVN: r768]]

[[Imported from SVN: r697]]

[[Imported from SVN: r695]]

[[Imported from SVN: r580]]