Reloading play project leads to JNotify Errors

Here's the output:

```scala
[error] (compile:run) java.lang.UnsatisfiedLinkError: Native Library /home/jsuereth/projects/test/reactive-maps/ReactiveMaps/target/native_libraries/64bits/libjnotify.so already loaded in another classloader
[error] Total time: 0 s, completed Apr 8, 2014 1:57:06 PM
```

Once I've managed to hack my classloader death-point (by modifying the build in just the right way), this is unrecoverable without killing the process.


Steps to reproduce:

1.  `$ sbt`
2. `> run`
3.  `ctl + D`
4. `> reboot`
5. `> run`

Guaranteed every time.  At a minimum, JNotify should be *optional* if the SO can't load.  At a maximum, Play should use the `~` feature *or* push JNotify requests upstream into sbt where we can use our native-library hackery so that reloading is ok.