Clarify in TracIni documentation how to set downloadable_paths for a multirepository environment

[Ryan J Ollos <ryano@…>]

I have a multirepository environment and was attempting to set the downloadlable_path option in the browser section. By trial and error, I arrived at the finding that I must prefix the repository name to these paths. It seems like it would be useful to add this to the documentation. Suggested addition in italics:

List of repository paths that can be downloaded. Leave the option empty if you want to disable all downloads, otherwise set it to a comma-separated list of authorized paths (those paths are glob patterns, i.e. "*" can be used as a wild card). In a multi-repository environment, the repository name must be prefixed to the paths (e.g. /repos1/trunk, /repos2/trunk) (since 0.10)

… or is this idea of prefixing the repository name to trac.ini options more obvious and I've overlooked it elsewhere in the documentation? In retrospect, I shouldn't be so surprised that I have to prefix the repository name, but the exact syntax for the prefixing wasn't obvious to me. At first I tried repos1:/trunk, before noticing that the path in the repository browser was /repos/trunk, which made the solution more obvious. It also wasn't obvious to me though that simply specifying /trunk, wouldn't make /trunk a downloadable path for the default repository.