Adding more fields to post_meta and one post_meta bug fix

• added secondary_language_bio to artist post_meta
• added description to workshop post_meta
• added performance_type to show post_meta
• fixed bug adding longitude to venue post_meta
Import Marcato Contacts and Vendors

Import Contacts and Vendors from Marcato XML for optional inclusion.
Merge pull request #6 from tflight/master

Pull in from Contacts and Vendors, add more fields from XML to post_meta