Minor inconsistencies in enums and schema

[vardumper]

1. Some attributes are defned as boolean, others that only have true/false values as enums (AriaBusyEnum, AriaHiddenEnum).
2. Some elements have attributes defined, that are at the same time defined as allowed_global_attributes. Remove from attributes in these cases.
3. Some attributes were moved to aria specs out of laziness, move to html5 specs.
4. Make generally more consistent.