RFR 8187305: Add logging for shared library loads/unloads

[Harold Seigel]

Hi,

Please review this small fix to add logging to loading, unloading, and 
finding entries in shared libraries.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8187305/webrev/index.html

JBS Bug: https://bugs.openjdk.java.net/browse/JDK-8187305

The fix was regression tested by running Mach5 tiers 1 and 2 tests and 
builds on Linux-x64, Solaris, Windows, and Mac OS X, by running Mach5 
tiers 3-5 tests on Linux-x64, and JCK lang and VM tests on Linux-x64.

Thanks, Harold