Update readme as an Ubuntu package has changed names.
Fix markdown in README
Update the README to use new package names only.

Ubuntu 11.04 is quite happy to use the new name, in fact the name
I originally used is a metapackage for the new name.
Add a section explaining how to run the examples.

This was explored in a thread, but now that it's been resolved it
makes sense to record the information more generally.
Note what the error looks like if you don't run ./shell
Added a greyscale IplImage index macro, KOKI_IPLIMAGE_GS_ELEM
Ensure greyscale image in koki_label_adaptive()
Use greyscale values in integral-image's update_pixel()
Use greyscale values in koki_threshold_adaptive_pixel()
Move threshold's classify_and_average() to greyscale
Moved koki_grid_from_image() to greyscale images
Ensure koki_marker_recover_code() receives a greyscale image
Ensure find_markers() and find_markers_fp() receive g/s images
Removed above_threshold function

It is now trivial to do the comparison manually since the image
must be greyscale.
Moved koki_label_image() to using greyscale images
Remove exposed RGB threshold fn. and convert threshold_frame to g/s
Convert older adaptive thresholding to greyscale
Update debug_img test to pass in g/s images
Converted speed_test to using greyscale images
Moved marker_info to using g/s images