[ISPN-4645] Many XSD default values do not match the defaults from the
corresponding configuration builder

Updated core XSD for state transfer chunk size property default value
ISPN-4961 Bump parsers and schemas to 7.1

- Altered org.infinispan.Version to retrieve the version using
maven-injection-plugin
- Improved SampleConfigFilesCorrectnessTest so that it accepts only
files with the latest schema
- Altered the documentation so that the version is dynamically replaced
- The Soft-Index File Store schema namespace was missing the "store" path
element. Added it for symmetry with all other store schemas.