ui: rewrite configint in terms of configwith

ui: add a configwith method This is a long-overdue generalization of the pattern in configint and configbool.

py3: convert the mode argument of os.fdopen to unicodes (2 of 2)

py3: convert the mode argument of os.fdopen to unicodes (1 of 2) os.fdopen() does not accepts bytes as its second argument which represent the mode in which the file is to be opened. This patch makes sure unicodes are passed in py3 by using pycompat.sysstr().

bugzilla: add a rest api backend (usable with bugzilla 5.0+) Add support for the bugzilla rest api documented at https://wiki.mozilla.org/Bugzilla:REST_API and at https://bugzilla.readthedocs.io/en/latest/ This backend has the following benefits: * It supports the bugzilla api keys so hgrc does not need to contain a user's bugzilla password * Works with Mercurial's "hostfingerprints" support making handling bugzilla instances with self-signed certs easier * Does not use xmlrpc ;-) Adds configuration item 'apikey' in [bugzilla] section. My major concern with these patches is if the approach to HTTP access is the right way for an extension and if hooking into request object and the overriding the get_method to perform PUT requests was a sensible approach. # no-check-commit

keepalive: honor urllib2 style get_method overrides In urllib2 docs and discussions it can be found that in order to make a request other than GET or POST the get_method of a Request object can be overriden. Make Mercurial's internal version of this honor the return value of get_method. Please see the followup patch to the bugzilla extension for the reason for this change. Marking RFC because I'm not entirely sure this is the right way make the HTTP requests.