[MINOR] Remove redundant links from docs index
[MINOR] Remove redundant links from docs index

Remove redundant links from docs index.
Remove 'Coming Soon' from PyDML Language Reference.
Replace Caffe2DML absolute reference with relative reference.

iyounus/incubator-systemml,asurve/systemml,dhutchis/systemml,dhutchis/systemml,deroneriksson/incubator-systemml,dhutchis/systemml,asurve/incubator-systemml,asurve/incubator-systemml,nakul02/incubator-systemml,asurve/arvind-sysml2,dusenberrymw/incubator-systemml,akchinSTC/systemml,dusenberrymw/incubator-systemml,niketanpansare/systemml,dusenberrymw/incubator-systemml,dusenberrymw/systemml,asurve/incubator-systemml,nakul02/systemml,sandeep-n/incubator-systemml,asurve/systemml,akchinSTC/systemml,gweidner/systemml,nakul02/incubator-systemml,akchinSTC/systemml,akchinSTC/systemml,deroneriksson/systemml,gweidner/systemml,asurve/systemml,deroneriksson/systemml,nakul02/systemml,nakul02/systemml,gweidner/incubator-systemml,nakul02/incubator-systemml,asurve/arvind-sysml2,gweidner/incubator-systemml,deroneriksson/systemml,akchinSTC/systemml,dusenberrymw/systemml,asurve/incubator-systemml,nakul02/incubator-systemml,dhutchis/systemml,deroneriksson/incubator-systemml,asurve/systemml,apache/incubator-systemml,iyounus/incubator-systemml,deroneriksson/incubator-systemml,dusenberrymw/systemml,iyounus/incubator-systemml,gweidner/systemml,dusenberrymw/incubator-systemml,iyounus/incubator-systemml,dusenberrymw/incubator-systemml,nakul02/incubator-systemml,asurve/arvind-sysml2,nakul02/incubator-systemml,niketanpansare/systemml,niketanpansare/systemml,akchinSTC/systemml,gweidner/incubator-systemml,iyounus/incubator-systemml,dusenberrymw/systemml,sandeep-n/incubator-systemml,gweidner/systemml,gweidner/incubator-systemml,dusenberrymw/systemml,gweidner/incubator-systemml,niketanpansare/incubator-systemml,asurve/arvind-sysml2,niketanpansare/systemml,apache/incubator-systemml,dusenberrymw/incubator-systemml,niketanpansare/incubator-systemml,deroneriksson/incubator-systemml,deroneriksson/systemml,apache/incubator-systemml,apache/incubator-systemml,asurve/arvind-sysml2,niketanpansare/systemml,apache/incubator-systemml,deroneriksson/systemml,dhutchis/systemml,sandeep-n/incubator-systemml,gweidner/systemml,sandeep-n/incubator-systemml,deroneriksson/incubator-systemml,asurve/systemml,gweidner/incubator-systemml,nakul02/systemml,deroneriksson/incubator-systemml,niketanpansare/incubator-systemml,deroneriksson/systemml,niketanpansare/incubator-systemml,asurve/arvind-sysml2,apache/incubator-systemml,iyounus/incubator-systemml,nakul02/systemml,dusenberrymw/systemml,gweidner/systemml,nakul02/systemml,asurve/incubator-systemml,asurve/systemml,niketanpansare/systemml,dhutchis/systemml,asurve/incubator-systemml