Specify woeid and units

For issue #2.  The dynamic_content:refresh fails (model validation) if you have old entries for the weather that used the obsolete zip_code field.  So you might want to db:reset before you test.

The WOEID lookup only shows the top five hits (when you tab out).  You have to enter a valid WOEID in the WOEID field to save the content, but you can type in anything and tab-out for the lookup.