CMosek added variable bounds

Hey @iglesias I made changes in Mosek.cpp for adding bounds on variables. Unfortunately, I have to touch many files to make the arguments consistent. Could you review the little patch for me? 

I am not sure we want to add unit-test for Mosek related class. But I am pretty sure these changes make sense. I have tested them on my own computer. BTW, I think @Jiaolong will test this part of code in his GraphCut inference thoroughly. 
I think that there should be somewhere a message or an error if the length of lb or ub is different from M. Otherwise, the user can do the set, training happens without setting the bound without the user being notified. Do you see my point, @hushell?