extmod/modurandom: Add "urandom" module.
Seedable and reproducible pseudo-random number generator. Implemented
functions are getrandbits(n) (n <= 32) and seed().
The algorithm used is Yasmarang by Ilya Levin:
http://www.literatecode.com/yasmarang
diff --git a/py/objmodule.c b/py/objmodule.c
index 32ded89..1034d00 100644
--- a/py/objmodule.c
+++ b/py/objmodule.c
@@ -184,6 +184,9 @@
#if MICROPY_PY_UBINASCII
{ MP_ROM_QSTR(MP_QSTR_ubinascii), MP_ROM_PTR(&mp_module_ubinascii) },
#endif
+#if MICROPY_PY_URANDOM
+ { MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&mp_module_urandom) },
+#endif
#if MICROPY_PY_USSL
{ MP_ROM_QSTR(MP_QSTR_ussl), MP_ROM_PTR(&mp_module_ussl) },
#endif