Fixed class version problems

For some reason the bex-1.1.jar released on Oct 1th only worked with JDK 1.6. With older JDKs it failed with: Exception in thread "main" java.lang.UnsupportedClassVersionError: Bad version number in .class file. I did a rebuild and uploaded a new bex-1.1.jar. Now it works in JDK 1.5 or later. It still fails to start with 1.4.2 since the new support for .bexrc uses System.getenv, which conveniently throws a java.lang.Error in JDK 1.4. This will hopefully be fixed in the next release 1.1.1. Other known bugs with release 1.1 are that \" or \$ character sequences are not allowed in multiline strings.