feat(bin/linja): add build_ninja_and_save_at

Fix #129
feat(frontends/lean/server): add timebound to WAIT command, closes #156

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(frontends/lean/server): unifier maximum number of steps error in FINDG, closes #155

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(bin/linja): allow non-exist cache argument

Fix #163
fix(bin/linja): pass args to call_lean and handle_failure_for_flycheck

Fix #163
fix(frontends/lean/parser): configuration options defined in a context are transient, fixes #162

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(frontends/lean/pp): pretty printing coercions to functions, fixes #151