fix(bin/lmake): missing case: no makefile & dir specified

close #27
test(tests/lean/interactive): add old 'interactive' tests

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean): add info_manager

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
refactor(frontends/lean): add 'server' module as a replacement for 'interactive'

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
chore(frontends/lean): fix style

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean/parser): save snapshots

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean): store 'overload' information, remove #setline

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean): save type information after elaboration, remove --flyinfo option

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(tests/lean): remove obsolete test

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>