Refactor/regex

[leissa]

This massages the regex code a bit.

• regex.thorin
  • use %core.idx instead of casts
  • use %core.mode.nuw for %core.wrap.add and %core.idx I actually experienced some serious performance issues some time ago, if this was missing, but I checked with the benchmark: doesn't do anything in our case
  • use more type aliases/functions
  • make use of ptrn groups
  • removed superfluous braces: {, }
  • use escaped chars (\t etc) instead of magic numbers
  • 1:.Bool -> .tt
• C++ files
  • use world.call instead of world.annex + world.app
  • removed now superfluous any_impl & co

[leissa]

brings us down from 323 -> 280 C++ loc :)

[fodinabor]

G'old LOC tuning :P