chore, check for mex.h in MATLABROOT/extern/include and set matlab_CFLAGS accordingly

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, use matlab_CFLAGS for tzconv mex DSO

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, refactor mex ldflags into MEX_LDFLAGS

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, talk about mexdir not moddir

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
fix, PEBKAC, move EXTRA_DIST specs out of conditional

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'contrib/mex-tzconv' into next

* contrib/mex-tzconv:
  fix, PEBKAC, move EXTRA_DIST specs out of conditional
  chore, talk about mexdir not moddir
  chore, refactor mex ldflags into MEX_LDFLAGS
  chore, use matlab_CFLAGS for tzconv mex DSO
  chore, check for mex.h in MATLABROOT/extern/include and set matlab_CFLAGS accordingly
Merge branch 'next'

* next:
  fix, PEBKAC, move EXTRA_DIST specs out of conditional
  chore, talk about mexdir not moddir
  chore, refactor mex ldflags into MEX_LDFLAGS
  chore, use matlab_CFLAGS for tzconv mex DSO
  chore, check for mex.h in MATLABROOT/extern/include and set matlab_CFLAGS accordingly