Make sure purge extension is available if we're to use it
ACCESS.CONFOut of the box, there are just two kinds of users: the ones with keys in"keys/root" and those in "keys/users". However, you can change this by editing"access.conf". There are two "access.conf" files, one in"/etc/mercurial-server" and one in "hgadmin"; the two are simply concatenatedbefore being read.Each line of access.conf has the following syntax:<rule> <condition> <condition> ...Rule is one ofinit - allow any operation, including the creation of new repositorieswrite - allow reads and writes to this file in this repositoryread - allow the repo to be read but reject matching writesdeny - deny all requestsA condition is a globpattern matched against a relative path. The two mostimportant conditions are user=<globpattern> - user's key repo=<globpattern> - repo (as the user supplies it)The first rule in the file which has all its conditions satisfied is used todetermine whether an action is allowed.Paths cannot contain any special characters except "/"; glob patterns cannotcontain any special characters except "/" and "*". "*" matches zero or morecharacters not including "/" while "**" matches zero or more charactersincluding "/".Blank lines and lines that start with "#" are ignored.access.conf ships with the following contents: init user=root/** deny repo=hgadmin write user=users/**This means: keys in "root" can do anything; keys in "users" cannot createrepositories, cannot even read the hgadmin repository, but can read and writeany other repository; no other key has any access.More advanced access configuration is covered in file-conditions.