Bump version number
Fixed issue #152 by replacing thread local variable with (threadsafe) singleton registry.
Support using the Validator.nu serializer for HTML; fixes issue #150
Fix issue #153; don't reset the base URI if the override base URI is the empty string
Fix bug (reported by Oxygen) where using the API to write a document resulted in an attempt to write to a closed handle
Fixed docs build process to work with the new double-repo approach
XML Calabash 1.0.18-95 released