Use shields.io for version badges [fixes #438]
Use shields.io for version badges [fixes #438]

shields.io seems to be the standard way to do badges now, and we don't
have to deal with caching issues of we're not serving the svg [#288]

codonnell/clojars-web,clojars/clojars-web,codonnell/clojars-web,clojars/clojars-web,xeqi/clojars-web,dotemacs/clojars-web,dotemacs/clojars-web,technomancy/clojars-web,tobias/clojars-web,nberger/clojars-web,ato/clojars-web,ato/clojars-web,tobias/clojars-web,xeqi/clojars-web,nberger/clojars-web,technomancy/clojars-web,tobias/clojars-web,clojars/clojars-web