oovar and oolin

I have committed my implementation of oovar and oolin to OpenOpt svn repository.

So, 2 new entries to oofun doc webpage have been added:

• using oovar (OpenOpt Variable)
  
• using oolin (that is linear oofun)

Currently oolin(f) returns (f, x) (that is numpy.dot). In future I intend to add c: oolin(f, c) is (f, x) + c.
Also, mb ooquad(H, f, c) will be implemented in future (that is 0.5 * x^THx + fx + c).