FindQuads has a resolution dependant pyramid

Instead of scaling 3 times the input image, a pyramid is built until the scaled
images are at least 320px wide.
Also, Canny edge detection is applied on each image of the pyramid, rather than
once on the binary image to be scaled down. This makes The edge detection more
robust to scale.

The performance increases most on high resolution images, which had tags to big
to be taken into account. The results are now comparable to LSD, without the
time penalty.

Before:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       3.1       0.7
 16    307200      11.5       5.7
  1   1228800      37.7       0.0
  3   1920000      46.2      12.3
  4   7990272     100.2       9.9
234/573 tags were not detected.

Now:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.2       0.4
 16    307200      10.2       4.0
  1   1228800      30.2       0.0
  3   1920000      46.5      14.2
  4   7990272     249.3      85.8
111/573 tags were not detected.

LSD:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800      16.9       6.3
 16    307200      56.0      19.9
  1   1228800     236.2       0.0
  3   1920000     806.3     728.5
  4   7990272    1798.5     285.8
141/573 tags were not detected.
Tweaked FindQuads: +20 true pos, +0 false neg

The tweak increases the tolerance in simplifying the contours into polygons
(possible quads).

Before:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.2       0.4
 16    307200      10.2       4.0
  1   1228800      30.2       0.0
  3   1920000      46.5      14.2
  4   7990272     249.3      85.8
111/573 tags were not detected.

Now:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.8       0.7
 16    307200      11.4       4.5
  1   1228800      33.6       0.0
  3   1920000      47.0      12.7
  4   7990272     285.7      98.7
91/573 tags were not detected.
Tweaked FindQuads: +2 true pos, +0 false neg

This tweak has a tiny effect on detection, but not so tiny on processing time...

Before:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.8       0.7
 16    307200      11.4       4.5
  1   1228800      33.6       0.0
  3   1920000      47.0      12.7
  4   7990272     285.7      98.7
91/573 tags were not detected.

Now:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.9       0.7
 16    307200      11.8       4.6
  1   1228800      34.2       0.0
  3   1920000      52.5      19.6
  4   7990272     298.4      97.4
89/573 tags were not detected.
Checking original quad too, not only refinements

+7 true positive, no new false negative

Before:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       2.9       0.7
 16    307200      11.8       4.6
  1   1228800      34.2       0.0
  3   1920000      52.5      19.6
  4   7990272     298.4      97.4
89/573 tags were not detected.

Now:
Processing times (ms) results, on 1 iterations:
  n    Pixels   Average        SD
  8     76800       3.4       0.8
 16    307200      12.5       4.8
  1   1228800      35.1       0.0
  3   1920000      53.7      20.2
  4   7990272     300.5      99.0
82/573 tags were not detected.
No more LSD

...no more funny commit messages
Merge pull request #24 from qbonnard/master

Optimized FindQuads. Possible SPEED optimizations are tracked in issue #26
updated copyrights
Written JNI bindings for most of Chilitags3D, usable in Android
Added RGB565 input image option besides YUV_NV21 for better (faster) OpenGL compatibility of the camera image
Turned off marker generator compilation during Android build
Wrote a barebone Android sample that receives the camera image and prints the tag transforms
Readme corrections
Changed the method of library installation inside Android project
Solved the .java files not found issue during make
OpenCV 3 works now, tested on 3.0-ocl-tp2
Wrote estimate3d-gui sample that displays the camera image and draws the tag reference frame arrows
Added a small fix to enable building JNI bindings on a host and not necessarily on Android
Added RGB888 for desktop compatibility, removed libopencv_info.so dependency
Readme changes
Huge speedup to the estimate3d-gui sample