Add MatlabInterface class files.

I forgot to add these files several commits ago so code would have broken on
any machine besides mine.
Merge remote-tracking branch 'oliverlee/fullorderobs' into full_order_observer
Bug fixes in Kalman measurement noise.

Previously, Kalman measurement noise was very very large, instead of very very
small.  This has the effect of not trusting measurements and instead trusting
the plant model more.  For some reason, we still cannot seem to estimate lean
-- the magnitude is always unreasonably small.
Gains generated using previous commit design parameters.
Merge remote-tracking branch 'oliverlee/fullorderobs' into full_order_observer
First quasi successful runs.

025.dat, 026.dat, 027.dat of 27JUN2013.
Two more quasi successful runs, 028.dat, 029.dat.

Going to revert the change and try only changing R so that we remove
saturation.
Runs 030.dat, 031.dat, 032.dat.
Run 033.dat through 037.dat of 28JUN2013.
Add LED indicators when lean and steer angles are small.

The purpose of this commit is to turn LED indicator lights on when the bike is
very close to the reference configuration; the hope is that by starting each
run at nearly the same initial configuration, we can obtain more consistent
behavior.
Fix static initialization bug that screwed steer angle calibration.

A namespace scope int32_t which was assigned the value of a constexpr for some
reason was not being initialized to the value of the constexpr. The result was
that the steer angle offset was being set to zero when the homefork function
was run, rather than set to the correct offset. This resulted in the "zero"
steer to be off by about 7 degrees.
Add working note on control of an unstable subspace.
Move illuminate to inline file; add control loop destructor.

Now LED's turn off when control loop object is destructed.
Add would_saturate() to Motor class.
Change std::fabs to std::abs.
Implement anti-windup with back caclulation.
Lean LED indication tested and verified.

Runs 000.dat through 003.dat.
Runs 004-006 from 29JUN2013 (early morning)
Record, but don't use, estimator state.

Record estimator state but use measurements and calculated lean angle,
steer rate as input to LQR controller.
Record rear wheel rate PI controller states.