Spark firmware v0.2.2

Changes

• New feature: Spark.subscribe() 👍
• Time now set by the Cloud when Core handshakes
• EEPROM emulation
• tone() and noTone()
• Arduino compatibility for constants in flash thanks to Jacob Rosenthal
• Arduino compatibility for generic clients thanks to Jacob Rosenthal
• Bugfix: Don't publish while updating firmware
• Upgraded CC3000 host driver to 1.12
• New patch updated sysflag to support deep update