Convert formulas to OLP commands in set-theory

[rzach]

Material from Tim Button in the set-theory part contains formulas. These have formulas hardcoded as \phi instead of !A etc, use \exists and \forall instead of \lexists and \lforall, don't use \eq for identity, and in some cases have atomic formulas without parentheses around arguments. To fix this, will need ability of \lforall and \lexists to have guards, e.g., \lforall(x \in \alpha)[!A(x)] should produce (\forall x \in \alpha), !A(x).