Launcher memory usage changes

ADDED: Java version display to options tab
ADDED: Console error message if Java registry entries are not found at all
CHANGED: Allow launcher to allocate up to 1.5gb of ram on 32-bit systems with > 2.5gb ram
CHANGED: Use 192mb PermSize for MC 1.6 and up on 32-bit systems with > 2gb ram (64-bit systems already use 256mb here)
CHANGED: Use 192mb PermSize for MC 1.5 or lower on all systems with > 2gb ram
CHANGED: Moved shared code to check total OS memory from OptionsPane to OSUtils