binary_heap: fix the heap property when inserting

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
tests: add macro to test if value is lower or equal than other value

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
binary_heap: implement core_binary_heap_delete_root()

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
tests: add tests for core_binary_heap_delete_root

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>