RFR: 8168911: Increased number of classes initialized during initialization of SignatureFileVerifier

[Claes Redestad]

Hi,

changes to SignatureFileVerifier in 9+142 has some startup implications, 
and a small
cleanup to avoid some trivial regexes etc reduces number of classes 
initialized in affected
startup tests by 61, undoing most of the observed regression.

Webrev: http://cr.openjdk.java.net/~redestad/8168911/webrev.01/
Bug: https://bugs.openjdk.java.net/browse/JDK-8168911

Thanks!

/Claes