Allow disabling dynamic plugins through a query parameter

The dynamic plugins enhancement describes a `disable-plugins` query parameter for disabling specific console plugins.

• ?disable-plugins or ?disable-plugins= prevents loading of any dynamic plugins (disable all)
• ?disable-plugins=foo,bar prevents loading of dynamic plugins named foo or bar (disable selectively)

This has no effect on static plugins, which are built into the Console application.

https://github.com/openshift/enhancements/blob/master/enhancements/console/dynamic-plugins.md#error-handling