[1/3] update openapi spec: update generator

Update the generator to be able to handle the new challenges that arose
with the new specification, namely:

- Enums that do not start with a capital letter
- Enums that contain a reserved keyword
- Basic handling 'allOf' keys in properties

Additionally, the comparison enum deserialisation is now
case-insensitive.

core/codegen/enum_header.hbs

@@ -4,8 +4,8 @@ public:
 	enum Value {
 		EnumNotSet,
 
-		{{#each values as |value|}}
-		{{value}},
+		{{#each entries as |entry|}}
+		{{entry.name}},
 
 		{{/each}}
 	};