Fix import paths

[klingtnet]

It is github.com/filebrowser/caddy... and not
github.com/filebrowser/filebrowser/caddy... .

[klingtnet]

The caddy build still crashes, but now with this failure:

.go/src/github.com/filebrowser/filebrowser/lib/file.go:195:15: undefined: parser.ReadFrom
make: *** [Makefile:10: caddy] Error 2

which corresponds to the godoc where no ReadFrom can be found.

[klingtnet]

The build.sh from this project fails with the same message:

# github.com/filebrowser/filebrowser/lib
../../.go/src/github.com/filebrowser/filebrowser/lib/file.go:195:15: undefined: parser.ReadFrom

[klingtnet]

Ok, there is already an issue filebrowser/filebrowser#554 regarding the build failure. You should think about using go modules to prevent this there's already an PR: filebrowser/filebrowser#496

[eine]

Thanks @klingtnet! Precisely, usage of go modules is discussed in filebrowser/filebrowser#496.