Feature/fix python constraints matrix

See merge request tools/frackit!131

Feature/new quad sampler

Closes #6

See merge request tools/frackit!130

This commit deprecates the old implementation that received a
distribution for the edge length, in favour of two distributions for the
characteristic dimensions in dip & strike direction. Internally, the new
polygon sampler is used, and when construction in the old way is
intended, a deprecation warning is thrown. However, this only works with
the default traits. Compilation will fail if custom traits were used...

Feature/polygon sampler

See merge request tools/frackit!129

This allows sampling the polygon corners without construction of the
polygon. Moreover, this commit introduces a check upon the sampling of
the polygon dimensions, in order for negative values to be discarded.
Sampling is tried 100 times, and if it was not successful an error is
thrown.

Feature/quad convexity check

See merge request tools/frackit!128

[python][point] register scale operator

See merge request tools/frackit!127

[multigeomentityset] use pointer instead of geom temporary

See merge request tools/frackit!126

When not using a pointer, compiler warnings related to default
construction of the geometries were printed when compiling with debug
flags. Using a pointer showed to compile without warnings even in debug mode.

Fix/quad poly center points

See merge request tools/frackit!125