"current features" include all lines of an ldf example

Number of current features (reported in the last column of vw progress) should include all features of multiline csoaa_ldf examples.
"current features" include also "shared" features in ldf examples

Number of current features (reported in the last column of vw progress)
should be the same no matter if we use "shared" features or manually copy those features to each line.
TODO: this still doesn't work with --quadratic and --cubic
beacuse VW::setup_example is called before the namespaces from "shared" are added via add_example_namespaces_from_example.
Merge pull request #448 from martinpopel/issue439

reported number of "current features" for ldf examples