Add tools and Makefiles for Documentation

This will allow us to start adding content and structure.
To generate documentation you will need to install both
- sphinx
- breathe

go into the doc directory and run:

$ make doxy html

No content has been submitted here, only a few placeholders.

Change-Id: Ifc3617aee8f7d45fa4e4a494ff0a1ab71516af06
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
diff --git a/.gitignore b/.gitignore
index 0a8c7ec..7c0710f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,3 +12,7 @@
 host/x86-linux2/bin/genOffsetHeader
 host/x86-linux2/bin/gen_config_abssym
 host/x86-linux2/bin/wrsconfig
+doc/_build
+xml
+html/
+doc/latex/