fix(navigation): revert changes to the page reset

Navigating to an empty data URL won't work for internet explorer, sadly.

Reverting to about:blank. Will watch for flakes and explore other options.
chore(release): version bump and changelog for minor release 0.23.1
fix(locators): fix by.repeater finding all rows for IE

Previously, element.all(by.repeater('foo in foos')) would find non-element
nodes for ng-repeat-start elements, which could cause IEDriver to fall over
if the test tried to get text from those nodes.
refactor(tests): cleanup and better separate protractor's basic test suite
chore(configuration): configuration syntax cleanup and better comments
chore(release): add a travis job to run smoke tests on more browsers

Adds smoke tests (not the full suite) that run on the latest 2 versions of
chrome, firefox, and IE.
fix(navigation): ignore unknown JS errors when looking for the URL

This should address #841

Ignoring the error and trying again has worked for all of my test cases,
and the error has never occurred more than once in a row.
test(config): added a common configuration environment.js
feat(launcher): Add support for maxSession

- add support for maxSession and capability-specific specs
- cleaned up launcher