Failures in the WFCORE test-suite with branch 1.x

Working on WFCORE-5773 I detected that current 1.x branch causes a lot of failures in the WFCORE test-suite. After investigating yesterday it is because of ELY-2271. Two problems:

• First the constructor for FileSystemSecurityRealm with signature FileSystemSecurityRealm(Path, NameRewriter, int, boolean, Encoding, Charset) has been removed and it's used here.
• Second there are several mechanism factories (for example DigestMechanismFactory) that changed the constructor from single Provider to a variable array argument. But this fails when called using reflection from here. So the original method should probably be put back (all the other providers implement that signature with one provider). This one took me more time.