Stop parsing install doc in FluidDoc, test=develop (#1564)

doc/fluid/beginners_guide/index_cn.rst

@@ -24,6 +24,5 @@ PaddlePaddle (PArallel Distributed Deep LEarning)是一个易用、高效、灵
     :hidden:
 
     quick_start_cn.rst
-    install/index_cn.rst
     basics/index_cn.rst
     programming_guide/programming_guide.md

doc/fluid/beginners_guide/index_en.rst

@@ -20,6 +20,5 @@ If you have been armed with certain level of deep learning knowledge, and it hap
 ..  toctree::
     :hidden:
 
-    install/index_en.rst
     basics/index_en.rst
     programming_guide/programming_guide_en.md