check-code: check for consistent usage of the websub filter in hgweb templates The check-code tool now expects the "desc" keyword to be followed by the "websub" filter, with the following exceptions: a) It has no filters at all, e.g. a changeset description in the raw style templates or the repository description in the summary page. b) It is followed by the "firstline" filter, e.g. the first line of the changeset description is displayed as a summary or title.

hgweb: apply websub filter to the changeset description in rss and atom feeds For example, this is useful for linking from the feed reader to a bug tracker. This follows the existing pattern used within the hgweb templates. With the exception of the raw style, all usages of the changeset "desc" keyword are now followed by either the "firstline" filter or the "websub" filter. When "websub" is used, it always follows the "escape" filter.

tests: write the hgrc file for test-hgweb-commands.t with cat instead of echo To improve the readability.