Merge branch 'mr/gitweb-jsmin'

* mr/gitweb-jsmin: gitweb: update INSTALL to use shorter make target gitweb: add documentation to INSTALL regarding gitweb.js instaweb: add minification awareness Gitweb: add autoconfigure support for minifiers Gitweb: add support for minifying gitweb.css Gitweb: add ignore and clean rules for minified files