Tests: remove "silent" option, "debug" should default to false
lib: drop the support for "silent" option + improved handling of "debug"
examples/pagesInCategory: turn off debug mode
lib/api: fix "Cookie has domain set to a public suffix" issue

@see https://github.com/mikeal/request/issues/792
Merge pull request #40 from macbre/no-noise-when-not-in-debug-mode

Don't print any debug information unless debug option is true