RuuviTracker Rev.C ideas

Some Lauri's notes about RuuviTracker's new HW design (Rev.C2 -> Rev.C3).

HW modifications

 * Fix inverter's schema component (pins 4 <-> 5)

Footprint fixes/mods

 * Publish footprint for both the header and receptable, preferably also publish design for a simple hirose to 2.54mm header breakout.

Possible Rev.C2's typos (needs to be checked before finishing Rev.C3 design)

 * LiPo charger behaves little weird sometimes without battery
 * Add here if you find something...

eLua problems...

 * Add here if you find something...