MVStore: use a separate write version for every map, so that the meta map version matches the version of the other maps.

Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).

there is no point in calling convertTo(Value.STRING) here, since we're just going to call getString() on the result

Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.

Replace Thread#sleep() with CountDownLatch
Original patch by Davide Cavestro, with some modifications by myself