Some tools get confused (google closure compiler, for example) when
there is a file in a jar and in a directory on the class path with the
same resource path. This commit addresses that issue.
Also, when we use other resources like images etc, it's important that
their paths relative to the HTML file are preserved, because css or js
might reference them. Tools like the boot cljs task will install
relevant files from cljsjs in the correct place, so we don't need to
make special modifications to the css or js in most cases (only when
they rely on absolute paths, which is terrible practice, anyway).
...nto fileset