Add support for wait/until functions with updated example code

[agilecreativity]

@tmarble
As I promised,

This PR is the improved version of wait/until function that I submitted earlier.
What has changes:

• Keep the original api intact if the user wants to use the old api
• Make it possible to wait for some event to happen before acting on it
• Much more efficient than using wait/sleep
• Simplify the logic for getting the chrome driver a bit to keep the code clean

Please let me know if you like any adjustment or if you have any comments.

Cheers,
Burin

[agilecreativity]

@tmarble
I commented out one test that is failing for now.
I added two more tests that is running properly with the new code.

it would be great if we could setup the CI/CD using something like CircleCI or TravisCI?

[tmarble]

@agilecreativity I really appreciate you working on this! I'm in the middle of making sure we can close #12 and I realized that webica got into a non-functional state. So yes, absolutely, I'd like to add TravisCI support (ideally with sauce labs too). I'm going to ask for your patience as I finish my PR for#12 and then we can look at this PR and rebase/adjust as required.

I'm looking at trying to coerce a vector of strings into a java.util.List<java.lang.String> to match this addArguments constructor.

In your changes is the notion of the 10 second timeout preserved in the wdriver?

[agilecreativity]

@tmarble

I think the timeout can be now set to the preferred time using the code here:

https://github.com/agilecreativity/webica/blob/master/src/webica/web_driver_wait.clj#L27-L40

Which can be override if desired.

The reference Java api is here:

https://github.com/SeleniumHQ/selenium/blob/master/java/client/src/org/openqa/selenium/support/ui/WebDriverWait.java#L35-L46

[agilecreativity]

@tmarble
Just wondering if you have any chance to take a look at the PR.
Thanks again for the great library.
Burin