Replace @VmParam with new functionality

```
@VmParam was based on a which centered around the flags as they are set rather
than the values observed by the JVM. It is being removed and needs to be
replaced. The required features are:
- The ability to specify lists of JVM flags to be combined, without specifying them on the command line. E.g. all combinations of -client or -server, -d32 or -d64 and -Xmx1g or -Xmx6g.
- The ability to specify default JVM flags for a benchmark. E.g. benchmarking a JavaAgent requires that the agent is enabled
- Possibly allow benchmarks to observe the values of the flags that are set.
```

Original issue reported on code.google.com by `gak@google.com` on 30 May 2012 at 8:52