First commit
failed try, could not get subwords in correct order if i prepended perm[:i] for small in smaller
sw works!!! At first level, if subword of exact same
length as a banned pattern the algorithm won't look further.

the next improvement will be to recursively use avoids before
prepending at any length of subword.
avoids_sw is working correctly. Next up is making
it recursively search for the banned patterns in
new subwords.
avoids_pos_ will look for all subwords containing perm[pos]
at the front and check if they are in the banned patterns
accidentally removed avoids_sw, reverted changes and added
avoids_pos_.
subwords_avoiding_ almost ready
subwords_avoiding_ is complete, takes in avoiding patts
parameter
avoids2_ is awesome, and super fast!
fast avoids2, about to change
the iteration through the 2d matrix
working, fast, O(n^2 choose(n, k))
faster implementation. constant append time, no calling is_in anymore
Merge branch 'master' of https://github.com/olafurpg/avoids

* 'master' of https://github.com/olafurpg/avoids:
  Initial commit