gitweb: make span.age CSS selector more specific This set of CSS properties is only used on /changelog page to make age elements float to the left and be fixed in size, but span.a is too broad of a selector, because we don't want to apply these properties to all <span> elements that have age class.

wireprotoserver: return to using iscmd() method This was teased out in part so remotefilelog could disable an old protocol method over http. It got dropped accidentally in the recent refactor, but the code was all still present so it's easy to support for now. I think once we land remotefilelog, we should probably inline this function. Differential Revision: https://phab.mercurial-scm.org/D2285

githelp: cast commands to bytes This is more compatible with Python 3. Differential Revision: https://phab.mercurial-scm.org/D2165