start -Dconfig.file from within activator broken

Play 2.3.1, activator 1.2.2.
```
> activator
$ start -Dconfig.file=local.conf
Configuration error: Configuration error["local.conf" : java.io.FileNotFoundException: "local.conf"  (No such file or directory)]
```
Note the double quotes and extra space: it is actually trying to open a file called '"local.conf" ' even though I put no quotes anywhere in the command and no space after conf.  Here is the relevant strace output:
```
22991 execve("/etc/java-config-2/current-system-vm/bin/java", ["/etc/java-config-2/current-syste"..., "-Xms1024m", "-Xmx1024m", "-XX:MaxPermSize=256m", "-XX:ReservedCodeCacheSize=128m", "-Duser.dir=/home/dylan/databrary"..., "-Dconfig.file=\"local.conf\" ", "-Dhttp.port=9000", "-cp", "/home/dylan/databrary/target/uni"..., "play.core.server.NettyServer"], [/* 41 vars */]) = 0
23054 stat("/home/dylan/databrary/target/universal/stage/\"local.conf\" ", 0x7f64242af2b0) = -1 ENOENT (No such file or directory)
23054 open("\"local.conf\" ", O_RDONLY) = -1 ENOENT (No such file or directory)
```
Using full paths does not help (it still double-quotes the whole path).