Use `RSpec.#{method}` for top level DSLs
e.g.
 * use RSpec.describe as opposed to describe
 * use RSpec DSL for shared examples
Configure whether to expose DSL globally
top level dsl under RSpec
describe behaviour with/without global namespace DSL
monkey patching must be explicity enabled if using same file *breaking change*
supress warning
expose globally true/false
spec out isolated expose globally on/off
describe at runtime configuration of global exposure