beta v 0.3.0

Complete rewrite to support multi-connection mode. Recommended upgrade.

• Changed API, see readme
• Changed name from Hologram800 to HologramSIMCOM
• Added ability to receive inbound data and SMS messages (close #1, close #2)
• Added blink example
• Removed ability to send traditional SMS, now only softSMS is available
• Added a few other functions, see readme