BlueDog V4: Unibody Quadcopter

This is the version 4 of http://www.thingiverse.com/thing:973089.

Some of the changes from previous version, after test flying:

• Increased inter-arm distance on each side to 120 MM from the center of motor shaft.

• Main plate is 50 MM shorter at 150 MM

• Arms are thinner now, for a better air flow

• Arms and Main Plate can be printed separately and glued together.