[Feature Addition] Compute Best Hypothesis Constrained within a Ball

[SWongHF]

Regret analysis is required. We are required to find the one single best vector minimizes the cumulative hinge loss, constrained in the feasible set $\mathcal{U}=\lbrace w:\lVert w\rVert_2^2\leq B\rbrace$, where $B=2$.

[firefox1347]

added the proposed changed in branch featureAddLoss