Fix linear SVM binding bugs

[rcurtin]

While trying to integrate linear_svm() into my company's software, I found two bugs; one simple, one rather subtle:

1. no_intercept is backwards---you have to specify no_intercept to get an intercept. This PR corrects the behavior. :)
2. The intercept was not properly being added in the call to Classify(). Specifically, we were using data.n_rows - 1 to get the index of the intercept in parameters---but if there is an intercept, then data has one fewer row than parameters! So we should use parameters.n_rows - 1 instead.

[KimSangYeon-DGU]

LGTM

[zoq]

Looks good to me as well.