fix for #5
replaced usage of incorrect Mtab.exp.name==xxx with Mtab.exp.has(name=x)
in ORM queries.
possible fix for #7, will take some time to test as "match_all_from"
is slow in SQLite.
added "test" command that repeatedly chooses an mtab at random
and then searches for matches, and when it finds one with matches,
prints it out and returns to the shell