v0.5.0

• New versioning
• Target#urls_from_page and Target#in_scope_urls renamed to Target#uris_from_page and Target#in_scope_uris. They also return/yield Addressable::URI instead of String. This reduces the object allocation of Addressable::URI in implemented scanners, and makes it easier to manipulate them (rather than having to re-parse the String with Addressable) - #91
• Target#in_scope? can now take an Addressable::URI or String as argument (was only String before)