1. Add a clustering demo, the link is
"http://shogun-toolbox.org/demo/clustering/entrance" 2. Add security
check for exceptional input. 3. fix the bug that the mouse can click
outside the coordinate system. 4 fix the range of the x-axis to 0..1 and
adjust the parameter of the svr demo.
Split the messy funtion into small ones.
Merge pull request #11 from foulwall/splitting-up

Clustering and SVR polishing
Merge branch 'master' into classification

Conflicts:
	pages/demos.py
	templates/demos/svr/index.html
Cleaning minor things.