Attempt to preserve the order in which packages are stored on the search path by preserving their order in `__packages`. It may not always keep the order where new packages are loaded in new chunks, but does appear to keep the order for multiple packages loaded within a chunk, or a series of chunks executed together. See http://stackoverflow.com/questions/26492875 for an example of the issue.
Merge pull request #867 from dgrtwo/master

Attempt to preserve the order in which packages are stored on the search...