try to inject only once, if needed...
so close but getting 'unexpected identifier' when selector has double quotes (") in it
working, with selector passed as arg, w/ s-w 2.4.2.
TODO: `all` (multi-element selector).
multi-element (`all`) finder with new approach.
take selenium-webdriver module as optional param and ensure instanceof.
tweak tests
bump version to 0.2.0
Merge pull request #6 from goodeggs/more-efficient

Be more efficient and performant by only injecting Sizzle once per page