Send an error if /add is accessed via a non-POST method.

Fixes #12.
Merge pull request #22 from eaburns/master

Check for POST
Merge pull request #23 from mccoyst/master

Check for valid / requests
Use NotFound method != POST in handleAdd.

This makes it consistent with method != "GET" in handleRoot.
Merge pull request #24 from eaburns/dev/eaburns

Use NotFound method != POST in handleAdd.
Don't serve tmplt files.
Require login in app.yaml.

Now we don't have to check it in the handlers.
Remove an old bug comment.
Merge pull request #28 from eaburns/dev/eaburns

Require login in app.yaml. Fixes #25. Fixes #26
Add feeds to the datastore.
Individual feeds are referenced by their key encoding.
Print the time feeds were fetched in the feed list.
Fix bug preventing feeds from being added.
Change the URL.

/	is all feeds
/<key>	is a single feed
/list	is the feed list
Merge pull request #31 from eaburns/dev/eaburns

Store feeds in the datastore and more
Change time formating to use functions instead of methods.

This way the functions can be shared, instead of reimplemented all the time.
Fixes #35
Only use one set of templates.
gofmt

Sorry.  I need to add the commit hook on this machine.
Get the user in the transaction to prevent a datarace.

If the user adds two feeds at once, they could lose one feed.
Limit to 50 feeds.

Fixes #30