pass "full_type" argument to proof reconstruction

made Sledgehammer's full-typed proof reconstruction work for the first time; previously, Isar proofs and full-type mode were mutually exclusive because both options were hard-coded in the ATP names (e.g., "e_isar" and "full_vampire") -- making the options orthogonal revealed that some code was missing to handle types in the proof reconstruction code

delect installed ATPs dynamically, _not_ at image built time