[Bro-Dev] script loading implementation

[Jonathan Siwek]

> Instead of going for the path you can go for the inode of the file.
> See man fstat(2). That will even take care of links.

This is what I ended up doing on Friday, just didn't commit yet because I was trying to figure out why one of the unit tests failed w/ that change.  Turns out the baseline was just wrong because the way the test file was named "conn-id.bro", it was loaded twice since the old path comparison method failed to detect a duplicate.

- Jon