Starting to formulate CBP

Still missing some constraints (they don't seem to be processed for the
moment anyway).
Merge commit 'c1ce1b87df53cced27e717dd50151cca2d2013e2' into cbp/1
Moved
Filled in remaining constraints
Fixed constraints using made up notation
Didn't mean to leave this here...
Or this
Finished "more natural" comment
Merge pull request #24 from chinasaur/cbp/1

continuous basis pursuit example.