use "lzma." prefix for LZMA-compressed embedded jars

Previously, we used "lzma:", which worked fine on Windows (where the
path separator is ";") but not on Unix-style OSes (where the path
separator is ":").  In the latter case, the VM would parse
"[lzma:bootJar]" as a path containing two elements, "[lzma" and
"bootJar]", which is not what was intended.  So now we use "lzma." as
the prefix, which works on all OSes.
preserve ThreadGroup.threadTerminated in openjdk.pro

We call this cleanup method from within the VM for every thread, so we
need to preserve it.
Merge pull request #160 from dicej/master

fix ProGuarded OpenJDK build and LZMA-compressed jar support