refactor(frontends/lean): rename action::is_compatible to action::is_equal

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean): allow user to provide a terminator for 'foldr' and 'foldl'

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(frontends/lean): remove keywords 'class' and '[class]'

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(build): add 'clean-olean' custom-target

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(frontends/lean/parser.cpp): fix typo
feat: add "--flycheck" option to print out error msgs for flycheck
fix(kernel/converter): missing constraints

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
refactor(library/unifier): process_flex_rigid method before adding yet another case split

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(library/error_handling): add flycheck_scope helper class

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(library/standard/list.lean): begin to port lists from lean 0.1
feat(library/standard/congruence.lean): add class to infer that a function is a congruence with respect to two relations
feat(library/standard/congruence.lean): finish congruence classes for propositional logic
index on master: 9dc1baa feat(library/standard/congruence.lean): finish congruence classes for propositional logic
feat(library/standard/list.lean): add facts about lists
refactor(library/standard): clean up logic, reorder arguments to elim rules