* Change the configuration for disabling components: instead of a `[disabled_components]` section that lists all components to be disabled, you can now enable/disable components in a `[components]` section. This also means that plugins need to be explicitly enabled for every environment. Closes #2019. * Support a global `trac.ini` configuration file (by default in `$prefix/share/trac/conf`). Closes #1051. Thanks to Alec Thomas for the patch.