Removed cyclic motion tracking example

The motion tracking example app is not needed at this time since there
is no filter which can do 10 DoF yet.
Removed Kalman filter and fusion header

Trying to implement a Kalman filter for an Arduino seems like a huge waste
of time. Removed the fusion header because users of this library should
only have to include what they use.
Cleaned up math

Most of the math functions in the utility folder are unnecessary for the
filter algorithms to function. Cleaned things up so only a more optimized
Quaternion class remains.
Updated license copyright year

Added 2014 to the copyright line.
Moved the Quaternion class

Got rid of the utility folder and moved the Quaternion class to the top
level directory in this Arduino library. Also fixed a Find-Replace error
where the include statement for quaternion.h got changed to q.h.
Added the new filter types

From now on this library will only be focusing on sensor fusion for 6 DoF
and 9 DoF systems. These new filters will only use Madgwick's math to
operate. This will help to make this library simpler to work with. Note that
as of this commit, the filter functions still need to be implemented.
Cleaned up doc folder

Removed Doxygen material for now. Changed the name of the External Articles
folder to articles.
Updated README.md

Cleaned up README text. Made it clear that only 6DoF and 9DoF systems can be
used with this sensor fusion library. After all, quaternions only
represent rotation. So why say we also plan on fusing cyclic motion and
global position (10 and 11 DoF) as well?
Removed unit testing

We don't need no stinkin' tests. But really, it will be obvious if this code
is not behaving at runtime.
Fixed compiler errors

Fixed typos and errors so this files will compile now.
Added functions for conversions

Added functions for converting from a quaternion to Euler angles and for
converting to an axis-angle. Tested these functions using Wolfram Alpha and
the quaternion 0.707107+0i+0j+0.707107k (+90 degrees yaw).
Fixed deltaTime variable name in Filter

Forgot to change occurences of deltaT to deltaTime in this file while
refractoring earlier.
Disabled Complementary filter code from compiling

Keeping this file only because it is necessary for understanding how to
write the new IMU and MARG filters. The change made was to prevent the
whole file from compiling using #if 0 directives.