Update the combined webapp struts.xml files to support the pb and pbtext
action extensions for protocol buffer data, as used on the
onebusaway-api-webapp.
Fix missing documentation for existing vehicles-for-agency action.
Document the GTFS-realtime export API.
Merge pull request #55 from bdferris/master

Fix missing documentation for existing vehicles-for-agency action.
Document the optional "time" parameter that is accepted by most OBA API
methods.
Merge pull request #56 from bdferris/api_timestamp_docs

Document the optional "time" parameter that is accepted by most OBA API methods.