2012-07-18 ago gracefully handle the case of empty theories when going up the accessibility chain
2012-07-18 ago renamed Sledgehammer options
2012-07-18 ago more code rationalization in relevance filter
2012-07-18 ago systematize lazy names in relevance filter
2012-07-18 ago rationalize relevance filter, slowing moving code from Iter to MaSh
2012-07-11 ago further ML structure split to permit finer-grained loading/reordering (problem to solve: MaSh needs most of Sledgehammer)
2012-07-11 ago split relevance filter code into three files