feat(library/kernel_bindings): add load method to Lua API

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(util/serializer): nontermination on corrupted files

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
test(tests/lean): new tests for exercising the environment object

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
test(tests/lean): new tests for exercising the environment object