Couple of fixes to ast.h
Couple of fixes to ast.h

1. ast_schema types field shouldn’t be of type enum json_type.  Its values will come from enum json_valuetype.  But b/c it can take OR’d values, it should probably be an int.

2. The field next in struct ast_property_schema should be of type struct ast_property_schema

3. Adds some includes so anything including ast.h will have the types it depends on declared.

sfstewman/jvst,sfstewman/jvst,katef/jvst,katef/jvst