This is a major rework of the remote repository detection mechanism within RBTools. The old implementation had a lot of issues, worst of which was that there was a lot of inconsistency across different tool implementations (for example, `rbt post` had a lot of additional detection code that wasn't shared with other tools). In the new implementation, we first try to fetch remote repositories, filtering by the configured repository name, or detected repository path(s). If this returns a single result, we can immediately return that. If that fails, it means we're in a situation where the configured paths on the server are different from the local path (including any mirror_path), and we need to match in a different way. Individual tools may implement `find_matching_server_repository` in order to do tool-specific comparisons (which right now is done by SVN with repository UUID and ClearCase with VOB UUID). This new method replaces the old `RepositoryInfo.find_server_repository_info` method, which always felt super ugly and clunky. In lieu of that, `RepositoryInfo` subclasses can implement `update_from_remote`, which allows them to include information from the remote repository or repository info resource. Commands which want to make use of the repository can now set the `needs_repository` attribute. In this case, the command initialization will handle finding the remote repository and updating the `RepositoryInfo` appropriately. This corrects a couple issues where commands were using the repository but forgetting to call the old `find_server_repository_info`, potentially ending up with incorrect data. The `setup-repo` command works a little differently because it needs to potentially do that multiple times, but it uses the same underlying mechanism to attempt to pre-filter the list of matching repositories in a useful way. This includes several other improvements and cleanups along the way: - Various places that fetch repositories to find matches have all been updated to use the locally detected tool to filter the response from the server. In the case where the server has a mix of repository types, this will dramatically improve the results. - `rbt setup-repo`'s server initialization has been fixed to merge handling of `--server` and interactive entry. This both improves the code, and has the side effect of making it so that if the server specified on the command line doesn't work, it will prompt the user. Testing Done: - Ran unit tests. - Verified that repository match fetches properly passed `tool=` for API requests to filter the responses based on the locally detected tool. - `rbt land`: Tested basic behavior. - `rbt patch`: Tested basic behavior. - `rbt post`: Posted new and updated changes against Git, including with `-u`. Created a remote SVN repository and posted purely remote commits using `--repository-url`. - `rbt setup-repo`: Tested with both `--server` and specifying the server name interactively. - `rbt stamp`: Tested basic behavior. - `rbt status`: tested both with and without `--all`. Verified that repository detection was making the most minimal API requests possible based on various .reviewboardrc configurations. Reviewed at https://reviews.reviewboard.org/r/11536/