Fix the GSM off issue and implement a simple workaround for the simcard logic issue.

INFORMATION ONLY, NOT TO BE COMMITED

There appears to be something wrong with the SimCard detection logic (simcard.c) that prevents SMS from sending.  The workaround is just to disable the check in the openstream handler.  This isn't a good long-term solution.

There was also an issue with gsm_off that prevented the module from actually turning off.  The module power pin was never released (on the old hardware this was accomplished by changing from digital to analog, but I guess that pin can't be analog on the new chip).  The fix here is to change the pin direction to input so the module turns off.