This addresses the following warnings from gcc-7:

    ../parallel/ddd/xfer/cmdmsg.cc:476:7: warning:
    unused variable ‘i’ [-Wunused-variable]

    ../parallel/ddd/xfer/pack.cc:395:48: warning:
    variable ‘recvProc’ set but not used [-Wunused-but-set-variable]

    ../parallel/ddd/xfer/unpack.cc:1226:7: warning:
    unused variable ‘lenSymTab’ [-Wunused-variable]

    ../parallel/ddd/xfer/unpack.cc:1482:9: warning:
    unused variable ‘ret’ [-Wunused-variable]

This way dependencies installed via `duneci-install-module` are built
with the same options as the module to be tested.

More cleanup

See merge request !70

This removes the following unused functions:

- `BVP_GetNext`
- `BVP_GetFirst`
- `BVP_GenerateMesh`

More cleanup

Closes #21

See merge request !69

Reference: #21

This removes various domains previously provided by UG.

To allow removing the files completely, a basic version of
`STD_BVP_Configure` is introduced in `std_domain.cc` as dune-grid
currently still ends up calling this code path.

Closes: #21

More cleanup, mostly compiler warnings

See merge request !68

dune-uggrid is always built for DUNE.

The code for volumes of tetrahedrons, pyramids and prisms should
always use 3D coordinates as it is really independent of the grid
dimension.

This addresses a number of warnings from clang-4.0 similar to:

    dune-uggrid/gm/evm.cc:426:21: warning:
    array index 2 is past the end of the array (which contains 2 elements)
    [-Warray-bounds]

The argument of `PRIO2INDEX` is only used in the parallel version of
UG; building the sequential version would raise a warning about `old`
being unused.

This change eliminates the `old` variables.

This addresses the following warning from gcc-7:

    dune-uggrid/gm/ugio.cc:1736:33: warning:
    variable ‘old’ set but not used [-Wunused-but-set-variable]

This change addresses several warnings from gcc-7 about unused
functions and variables:

    dune-uggrid/gm/algebra.cc:297:12: warning:
    ‘UG::INT DisposeIMatrices(UG::D3::GRID*, UG::D3::MATRIX*)’ declared ‘static’ but never defined [-Wunused-function]

    dune-uggrid/gm/algebra.cc:5056:13: warning:
    ‘void GetBVNumber(UG::D3::BLOCKVECTOR*, UG::INT*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/algebra.cc:5045:13: warning:
    ‘void GetBVNumberInGrid(UG::D3::GRID*, UG::INT*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/algebra.cc:5033:12: warning:
    ‘UG::INT CheckBVList(UG::D3::GRID*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/algebra.cc:5013:12: warning:
    ‘UG::INT CheckVectorList(UG::D3::GRID*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/algebra.cc:4981:12: warning:
    ‘UG::INT CheckConsistence(UG::D3::GRID*, char*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/algebra.cc:310:13: warning:
    ‘void CheckMatrixList(UG::D3::VECTOR*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/ugio.cc:2803:19: warning:
    variable ‘id’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:2540:9: warning:
    unused variable ‘q’ [-Wunused-variable]

    dune-uggrid/gm/ugm.cc:2707:22: warning:
    variable ‘NFather’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:4172:9: warning:
    variable ‘fineGrid’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:4424:8: warning:
    variable ‘theBVP’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:4425:13: warning:
    variable ‘theBVPDesc’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:5793:7: warning:
    unused variable ‘retval’ [-Wunused-variable]

    dune-uggrid/gm/ugm.cc:7347:8: warning:
    variable ‘theBVP’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/ugm.cc:7214:13: warning:
    ‘void CalculateCenterOfMassOfSide(const ELEMENT*, int, UG::DOUBLE*, UG::DOUBLE*)’ defined but not used [-Wunused-function]

    dune-uggrid/gm/refine.cc:1367:9: warning:
    variable ‘NbSidePattern’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/gmcheck.cc:1183:24: warning:
    variable ‘bserror’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/gm/er.cc:1777:15: warning:
    variable ‘nfound’ set but not used [-Wunused-but-set-variable]

    dune-uggrid/np/udm/udm.cc:3929:13: warning:
    variable ‘off’ set but not used [-Wunused-but-set-variable]

all dim-indep objects should be only in one library

See merge request !66

Variables from dim-indep objects would exist multiple times.  Which
copy gets used depends on linker details.

When I used dune-corepy on an old Ubuntu 14.04 installation, different
copies of variables would be used in different places in the same
program, causing the program to misbehave.

This change moves all dim-indep objects into a single library which
should avoid such problems.

More cleanup

See merge request !65