chore, outsource asm coru option guts (rename to --enable-*) into m4

Signed-off-by: Sebastian Freundt <hroptatyr@fresse.org>
chore, update travis file to build both asm and slju coroutines

Signed-off-by: Sebastian Freundt <hroptatyr@fresse.org>
Merge branch 'bld/dist'

* bld/dist:
  chore, update travis file to build both asm and slju coroutines
  chore, outsource asm coru option guts (rename to --enable-*) into m4