DOC: repositioned tracking quick start in examples_index
DOC: added proper reference link from tracking_quick_start to new tracking API
DOC: added contents and highlighted new example sections
Merge pull request #514 from Garyfallidis/website-update-20Dec2014

Website update
RF - renamed MaximumDeterministicDirectionGetter to DeterministicMaximumDirectionGetter
DOC - added example for deterministic maximum direction getter
DOC - fixed typos
DOC - fixed typos
RF - changed tabs to spaces
RF - update deterministic tracking example
Merge pull request #495 from gabknight/nf_add_maximum_det_dg

NF - Deterministic Maximum Direction Getter