Normalized references to extension schemas using the following rules:

- Schemas are localized into the "external" folder using their exact version (including update version)
- Extension filenames match the exact version (including the update version)
- Extension namespaces and type names use the major.minor version but not the update version
Remove import of CAPEC extension from STIX Phishing Indicator

The STIX Phishing Indicator sample imported the CAPEC extension but never actually used it. This removes the import.