Switch selenium tests to use implicitly_wait() instead of custom wait functions.

[Tim Graham]

From the selenium docs, "Dependent on several factors, including the OS/Browser combination, WebDriver may or may not wait for the page to load. In some circumstances, WebDriver may return control before the page has finished, or even started, loading. To ensure robustness, you need to wait for the element(s) to exist in the page using ​Explicit and Implicit Waits."

Currently, we have a collection of ​wait_for* methods to accomplish this. The idea is to switch our code to call self.selenium.implicitly_wait(10) after initializing self.selenium which should allow us to remove many of these waiting calls.