namespaces: copy implementation to new namespace object

namespaces: add a namespace object Currently, we use a dictionary object to store the namespace properties. This is python so let's use an object. This will allow us to be more flexible in our method signatures in the future.

localrepo: use vfs.reljoin rather than os.path.join in the localrepository class The removes the last remaining usage of os.path.join inside teh localrepository class.

largefiles: drop a redundant check for patterns when removing without --after This is in the way of passing a matcher to removelargefiles(). This method is called in exactly two places- first in overrides.addremove() (but only if the pattern list passed to it is not empty), and second in the commands.remove() override. But since the latter calls commands.remove() first, which also does this check, it isn't needed here.

context: override _dirstatestatus in workingcommitctx for correct matching Before this patch, the result of "status()" on "workingcommitctx" may incorrectly contain files other than ones to be committed, because "workingctx._dirstatestatus()" returns the result of "dirstate.status()" directly. For correct matching, this patch overrides "_dirstatestatus" in "workingcommitctx" and makes it return matched files only in "self._status". This patch uses empty list for "deleted", "unknown" and "ignored" of status, because status between "changectx"s also makes them empty.

context: avoid breaking already fixed self._status at ctx.status() Before this patch, "status()" on "workingcommitctx" with "always match" object causes breaking "self._status" in "workingctx._buildstatus()", because "workingctx._buildstatus()" caches the result of "dirstate.status()" into "self._status" for efficiency, even though it should be fixed at construction for committing. For example, template function "diff()" without any patterns in "committemplate" implies "status()" on "workingcommitctx" with "always match" object, via "basectx.diff()" and "patch.diff()". Then, broken "self._status" causes committing unexpected files. To avoid breaking already fixed "self._status" at "ctx.status()", this patch overrides "_buildstatus" in "workingcommitctx". This patch doesn't write out the result of template function "diff()" in "committemplate" in "test-commit.t", because matching against files to be committed still has an issue fixed in subsequent patch.