Updated docs to explain "intents" section in extension manifest.

chrome/common/extensions/docs/README.txt

 This directory contains the chromium extensions documentation, and the mechanism
 by which they are generated.
 
 --------------------------------------------------------------------------------
 Contributing To The Extension Docs:
 
 [When making changes, open the relevant /<page>.html in chrome via the file:
 scheme. If you do, you can refresh to instantly see any changes you make].
 
 *I want to document methods, events or parameters in the api itself:
 =>Edit the JSON file for the api in ../api/. Usually you can just add or edit
 the "description" property. This will appear automatically in the corresponding
 doc page at ./<page>.html (where <page> is the name of the apimodule ("tabs",
 etc..) that contains the change you are making.
 
 *I want to edit static content for an API reference module:
 =>Look in /static/<page>.html (for your module). If the file exists, edit it,
 check you changes by viewing /<page>.html. If the file doesn't exist, add it,
 and make a copy of /template/page_shell.html and copy it to /<page>.html.
 
 *I want to edit or add a purely static page:
 =>Follow the same steps for editing static content for an API page.
 
-IN ALL CASES. When you have finished, run build/build.bat (on windows) or
-build/build.py (on mac/linux). This may generate new files or changes to the
+IN ALL CASES. When you have finished, run ./build/build.bat (on windows) or
+./build/build.py (on mac/linux). This may generate new files or changes to the
 /*.html pages. Include any new or changed files in the changelist you create.
 
+When submitting changes for review, please host the contents of your version
+of chrome/common/extensions/docs on a web server accessible to your reviewer.
+
 --------------------------------------------------------------------------------
 Building
 
 Changes to the extension docs must be checked into source control. Any changes
 to any input sources require the docs to be regenerated.
 
 To build the extension docs, run the build.py script in the ./build directory.
 This will regenerate the docs and report which, if any, files have changed
 and need to be included in the changelist that changed the dependent files.
 
@@ skipping 26 matching lines @@
 For each given <page>:
 1) A copy of ./page_shell.html is copied to ./<page>.html.
 2) This page loads bootstrap.js which inspects the <page> name
 3) ./template/api_template.html is loaded and inserted into the body of the page
 4) If a ./static/<page>.html exists, its content is inserted into the main
 content column of the api_template.html
 5) If the <page> matches an api "module" in ../api/, the api is then
 fed through the api template within api_template.html
 6) The result is written on top of the existing /<page>.html. If the new file
 differs in content, it is reported as changed by the build.py script.