Allow arbitrary case for element names

[joshsh]

Hydra currently makes some assumptions about case conventions for element and field names, e.g.

• The local part of type names are in PascalCase
• The local part of non-type element names are in camelCase
• Field names are in camelCase

While these may be considered as best practices for models defined natively in Hydra, the only hard and fast rule should be that names contain only alphanumeric ASCII characters and underscores in their local part, while slashes '/' are also allowed in the namespace part. Certain lexical operations are currently broken by models which do not follow the best practices described above, and this should be fixed.

[joshsh]

There is actually nothing which enforces case conventions in Hydra Names any more. Closing this old ticket.