docs, readme: Update branch references for rocko

Signed-off-by: Paul Barker <pbarker@toganlabs.com>

README.md

@@ -33,12 +33,12 @@ OpenEmbedded/Yocto distributions and layer stacks, such as:
 This layer depends on:
 
 * URI: git://git.yoctoproject.org/poky
-  * branch: master
+  * branch: rocko
   * revision: HEAD
 
 * URI: git://git.openembedded.org/meta-openembedded
   * layers: meta-oe, meta-multimedia, meta-networking, meta-python
-  * branch: master
+  * branch: rocko
   * revision: HEAD
 
 ## Quick Start

docs/conf.py

@@ -58,9 +58,9 @@ author = 'meta-raspberrypi contributors'
 # built documents.
 #
 # The short X.Y version.
-version = 'master'
+version = 'rocko'
 # The full version, including alpha/beta/rc tags.
-release = 'master'
+release = 'rocko'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.