add (presumably) working theme-entry substrings code (O(kn^2), k theme entries (of length O(n)))
add (presumably) working theme-entry substrings code (O(kn^2), k theme entries (of length O(n)))

horwitz/mechapuzzle,boisvert42/mechapuzzle,boisvert42/mechapuzzle,horwitz/mechapuzzle