removed magic numbers and added comments to Zuid
fix unused UID_FORMAT string
added reference to current account into swift:// urls

now user can reference a current account id path with "." (dot)
Like this:

swift://./container/object

Can be used in job descriptions and zapps
Merge pull request #15 from pkit/job_manager_2

 removed magic numbers and added comments to Zuid
Merge pull request #14 from pkit/proxy_fixes

added reference to current account into swift:// urls
cleaned up content_type handling for requests and responses

added content_type property to swob.Request class
Merge pull request #16 from pkit/proxy_fixes

cleaned up content_type handling for requests and responses
more cleanup for content_type handling
Merge pull request #17 from pkit/proxy_fixes

more cleanup for content_type handling