x_t parameter not needed for authentication url
(fix) server doesn't return x_t, so this would never work

also, it wasn't even used
 (fix) Move timestamp into createAuthenticatedUrl from the constructor so that UserContexts don't become stale
Merge pull request #15 from omsmith/removeServerOffset

(fix) server doesn't return x_t, so this would never work
Merge pull-request #16 from jparker-d2l/timestamp-fix

Conflicts:
	lib/valence.js
(tests) add more tests. everything but createAuthenticatedUrl
Merge pull request #17 from omsmith/moreTests

(tests) add more tests. everything but createAuthenticatedUrl
assume nodejs and provide browser build with browserify
parse url params using url module
use url module to build targetUrl
testling setup
move the browser specific code to it's own file

only exists for backwards-compatability with expectation of it being merged onto the global
if we could just overwrite window.D2L, then browserify would do this for us