localrepo: make supported features manageable in each repositories individually Before this patch, all localrepositories support same features, because supported features are managed by the class variable "supported" of "localrepository". For example, "largefiles" feature provided by largefiles extension is recognized as supported, by adding the feature name to "supported" of "localrepository". So, commands handling multiple repositories at a time like below misunderstand that such features are supported also in repositories not enabling corresponded extensions: - clone/pull from or push to localhost - recursive execution in subrepo tree "reposetup()" can't be used to fix this problem, because it is invoked after checking whether supported features satisfy ones required in the target repository. So, this patch adds the set object named as "featuresetupfuncs" to "localrepository" to manage hook functions to setup supported features of each repositories. If any functions are added to "featuresetupfuncs", they are invoked, and information about supported features is managed in each repositories individually. This patch also adds checking below: - pull from localhost: whether features supported in the local(= dst) repository satisfies ones required in the remote(= src) - push to localhost: whether features supported in the remote(= dst) repository satisfies ones required in the local(= src) Managing supported features by the class variable means that there is no difference of supported features between each instances of "localrepository" in the same Python process, so such checking is not needed before this patch. Even with this patch, if intermediate bundlefile is used as pulling source, pulling indirectly from the remote repository, which requires features more than ones supported in the local, can't be prevented, because bundlefile has no information about "required features" in it.