Distance Transform tutorial fixes

Distance Transform fixes v.2

Distance Transform fixes v.3

Distance Transform fixes v.4

literalinclude

literalinclude, dropped :lines:

In section "How do we get an Affine Transformation" subsection 2 there was a ' where there should have been a ` which caused the math to be rendered incorrectly.

e.g. <opencv2/core/core.hpp> become <opencv2/core.hpp>

Also renamed <opencv2/core/opengl_interop.hpp> to <opencv2/core/opengl.hpp>

updated links in cheatsheet
renamed directory for Mat tutorial 
changed links from willow docs to opencv.itseez.com, from Trac to current Redmine

Added the "Mask operations on matrices" tutorial (with its sample). Plus modified some other core tutorials.

Ok, now optimized the tutorial size for real. Made JPG/PNG optimization for all the images. Modified some tutorial files to follow these size optimizations. Now the tutorial PDF generated is 3.95MB, so enjoy!

2) Added a raw Latex page break directive after each TOC tree. (For the PDF tutorial look).
3) Two finished tutorials: 
   a) one describing how the Mat data structure works and its output capabilities (format function) (demonstration YouTube video included).
   b) one describing image scanning operations plus the LUT function (demonstration YouTube video included). 
   c) a basic filtering approach (plus multi row image scanning demonstration) in the work.

Added reST tutorials for Contours (6 in imgproc) and for Corner Detection (4 in features2D) + links in conf.py