Add an interface to load files with.

This allows loading from other than raw files.
Consistently use FileLoader for standard ISOs.
Make LocalFileLoader essentially private.
Kill FileLoader::Reopen()...

Was a bad idea.
Add an HTTP transport for loading isos.

Not exposed in UI yet, but you can use command line.
Implement a simple recently used cache for HTTP.
Oops, don't try to read past end of file.
Add a readahead cache for HTTP.

So the only other thing it could do is idle backfill...
Update native with HTTP fix.
Fix a possible leak.

Can definitely see this happening.
Treat generation 0 a bit specially.

I guess we could always check gen 0 first, that'd be readahead/backfill.
Handle case in HTTP headers better.
Fix disconnect order.
Add more verbose logging in case of error.
Shortcut a read outside the file.

This happened to me.
Add an interface to retry HTTP requests.

They could fail / be spotty in some situations.  A little retry can go a
long way.
Merge pull request #7106 from unknownbrackets/file-remote

Use an interface to read iso files, not raw file reading
Don't try to close invalid files.
Oops, typo.
Buildfix for Linux and Symbian.