Bug 522083 - Simplify StringUtils classes

No need for multiple concat methods - just use varargs.
No need for split method - pre 1.4 JVM is not supported now.

Change-Id: I1c1e349746d7c817933c1451393b8abfd67ba37a
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>
8 files changed