ISPN-4204: Sync distexec demo project with current test code

Add a no argument constructor to WordCountCollator
Add a new distributed executor that performs a regular expression search
of the values in the cache
Reset counters in constructor for WordCountMapperEmitPerValue, and only
log progress after processing 5000 values
ISPN-4216 Use IGNORE_RETURN_VALUES flag for inserting keys/values in M/R intermediate cache
ISPN-3689: Preloading fails with JdbcBinaryCacheStore on DB2 (master)
ISPN-4214 Custom cache store and cache loader sets SHARED attribute to the value of NAME attribute
Fix the extended statistics tests broken by the ISPN-2148 fix
ISPN-4221 Make the authorization configuration implicitly enabled by the presence of the "authorization" element
ISPN-3877 - SingleFileStore continues to consume space on the disk even if the free entries at end of the file are not in use
Properly fix the server testsuite by making it use the 7.0 schema (instead of downgrading the distributed configuration schema)
ISPN-4205 Security integration test for kerberos + LDAP