Rename our test module
Disambiguate figure appearance

See 882b5d0.
Fix the configuration script for METAPOST tests

This is a leftover of 7065536.
Add a testcase for METAPOST figures with TeX labels
Rely on MPINPUTS to let METAPOST locate source files
Specify the TeX engine used by METAPOST

Some ditributions of TeX use by default a non-existent TeX engine
in METAPOST.
Remove obsolete METAPOST to PostScript conversion routine

The output of METAPOST is now Encapsulated PostScript, it is enough
to copy files to achieve a conversion.
Add a galley mode so that LaTeX errors and warning are not fatal
Look for METAPOST files in the the MPINPUTS path
Merge branch 'topic/texmf-metapost-improve-tex'
Conditionally recreate object directories