Fix XSD/RNG for Inventory/HotelInfo ContactInfo URL ID
requested to merge gappc/standard-specification:57-fix-inventory-contactinfo-url-id-restriction into 2020-10-errata-corrige
The written 2020-10 standard says on page 55, that "...Partners are allowed to define further values...". Unfortunately, the XSD and RNG files restrict the ID values to be exactly one of the following values:
- WEBSITE
- TRUSTYOU
- TRIPADVISOR
- YOUTUBE
This commit loosenes that restriction and allows arbitrary upper-case string values.
Closes #57 (closed)