Update key-tool plugin to work on jdk8
Fix JarSigner to work with JDK7 & 8
Merge pull request #5880 from ctomc/jdk8

Last fixes to make testsuite work on JDK8
[WFLY-1523] Introduce caching for LDAP access by security realms for user searching, caching validated passwords and caching the results of group searches.
[WFLY-1523] Some minor modifications following code review of the LDAP cache implementation.