Add some initial reference documentation

doc/requirements.txt

 sphinx
-git+https://github.com/arximboldi/breathe@fix-node-parent
+breathe==4.9.1
+# git+https://github.com/arximboldi/breathe@fix-node-parent

doc/src/conf.py

@@ -152,5 +152,6 @@ texinfo_documents = [
      'Miscellaneous'),
 ]
 
-
+breathe_default_members = ('members', 'undoc-members')
+cpp_index_common_prefix = ['migraph::']
 

doc/src/index.rst

@@ -10,6 +10,8 @@ Welcome to MIGraph's documentation!
    :maxdepth: 2
    :caption: Contents:
 
+   reference/data
+   reference/operators
 
 
 Indices and tables

doc/src/reference/data.rst

+Data types
+==========
+
+shape
+-----
+
+.. doxygenstruct:: migraph::shape
+
+literal
+-------
+
+.. doxygenstruct:: migraph::literal
+
+argument
+--------
+
+.. doxygenstruct:: migraph::argument
+
+raw_data
+--------
+
+.. doxygenstruct:: migraph::raw_data
+
+.. doxygenfunction:: migraph::visit_all
+
+
+tensor_view
+-----------
+
+.. doxygenstruct:: migraph::tensor_view

doc/src/reference/operators.rst

+Operators
+=========
+
+operation
+---------
+
+.. doxygenstruct:: migraph::operation
+
+operators
+---------
+
+.. doxygenfile:: operators.hpp