Create ProfileIdentifierType.md (#249)

* Create ProfileIdentifierType.md

An arbitrary string for profile identifier, is going to cause too many snags, with arbitrary matching and capitalization.     Recommend restricting this down to the agreed on set of formal names for profiles.

* Update profile.md

Change range to be a ProfileIdentifierType rather than an XSD string type.

* Delete ProfileIdentifier.md

Make the profile identifier a set of enumerated values, rather than arbitrary string.    Added a Vocabulary of ProfileIdentifierType and remove the class which references a string type.

model/Core/Properties/profile.md

@@ -14,5 +14,5 @@ This field provides information about which profiles the Element belongs to.
 
 - name: profile
 - Nature: DataProperty
-- Range: ProfileIdentifier
+- Range: ProfileIdentifierType
 

model/Core/Vocabularies/ProfileIdentifierType.md

@@ -0,0 +1,27 @@
+SPDX-License-Identifier: Community-Spec-1.0
+
+# ProfileIdentifierType
+
+## Summary
+
+Enumeration of the valid profiles that an element can be specified to be part of. 
+
+## Description
+
+There are a set of profiles that have been defined to be valid for a specific release   This file enumerates the values that have been agreed on, and may be applied to the creation information for an an element.
+
+## Metadata
+
+- name: ProfileIdentifierType
+
+## Entries
+
+- core: TODODescription
+- software: TODODescription
+- licensing: TODODescription
+- security: TODODescription
+- build: TODODescription
+- ai: TODODescription
+- dataset: TODODescription
+- usage: TODODescription
+- extension: TODODescription