reversed popup communication, no longer use postMessage
use ie-compatible window.location.origin for redirectUri
check if window.atob exists
readme: updated browser support
readme: updated table of contents
Merge remote-tracking branch 'origin/master'
readme: center align browser versions
inline redirectUri fallback to make it clear
readme: updated configuration
code cleanup
added loginOnSignup unit test
removed redunant isAuthenticated test
updated tests
pass userData parameter to link()

Fixes #130
IE8 support: reaplaced promise.catch with promise.then(null, function)
v0.7.0
readme: updated api
readme: updated $auth.link description