Update hackney dependency

Change-Id: I802af2a4b92ddf8920b0068a1810ba487f254c81
Format stacktrace lines with no file

Change-Id: Ia20e2f06f72a4cf4c0aadd4e5b98f6a9d44580ef
Use HTTPoison.Base

Change-Id: I61875e02a92fb4f4645b930ba3d47844453266de
Add some super fragile temporary tests
Relax Elixir version requirement
Trade in catch for try
Remove overly fragile broken tests
Change public API

Now we expose a report/2 that takes an Exception and the stacktrace.
Bump to v0.1.0-dev
Remove debugging calls
Refactor Bugsnag.payload

Change-Id: I65c5f246fbfe99c0d258715603c9e05427be3562
Expose payload construction and test stacktraces
Test API key is present in payload
Test notifier is present
Report version and Github link from Mixfile
Add a few more tests
Remove substantial duplication from tests
Stay safe against bad input
Added support for context (needs refactor)
Fix bug in stacktrace formatter