add doxypypy and py_filter so this will turn google style

docs/Doxyfile

 # Doxyfile 1.8.6
 
 # This file describes the settings to be used by the documentation system
 # doxygen (www.doxygen.org) for a project.
 #
 # All text after a double hash (##) is considered a comment and is placed in
 # front of the TAG it is preceding.
 #
 # All text after a single hash (#) is considered a comment and will be ignored.
 # The format is:
@@ skipping 856 matching lines @@
   InTodoBlock { $0 = gensub(/ (TODO[ (:])/, \" @todo \\1\", \"g\", $0); }      \
   { print; }'"
 
 # The FILTER_PATTERNS tag can be used to specify filters on a per file pattern
 # basis. Doxygen will compare the file name with each pattern and apply the
 # filter if there is a match. The filters are a list of the form: pattern=filter
 # (like *.cpp=my_cpp_filter). See INPUT_FILTER for further information on how
 # filters are used. If the FILTER_PATTERNS tag is empty or if none of the
 # patterns match the file name, INPUT_FILTER is applied.
 
-FILTER_PATTERNS        =
+FILTER_PATTERNS        = *.py=./py_filter
 
 # If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using
 # INPUT_FILTER ) will also be used to filter the input files that are used for
 # producing the source files to browse (i.e. when SOURCE_BROWSER is set to YES).
 # The default value is: NO.
 
 FILTER_SOURCE_FILES    = NO
 
 # The FILTER_SOURCE_PATTERNS tag can be used to specify source filters per file
 # pattern. A pattern will override the setting for FILTER_PATTERN (if any) and
@@ skipping 1438 matching lines @@
 
 CLANG_ASSISTED_PARSING = NO
 
 CLANG_OPTIONS = "-std=c++11" \
                 "-DALLOW_DUMP=1" \
                 "-DALLOW_LLVM_CL=1" \
                 "-DALLOW_LLVM_IR=1" \
                 "-DALLOW_LLVM_IR_AS_INPUT=1" \
                 "-DALLOW_MINIMAL_BUILD=0" \
                 "-DPNACL_BROWSER_TRANSLATOR=0"