Specify types in escalus_config
Extend Makefile with dialyzer and typer rules
Typespec escalus_session
Be explicit about the deps to base dialyzer PLT on
Refactor auth_sasl_scram_sha1/2
Simplify escalus_stanza:auth / :auth_response and fix dialyzer warnings
Fix typo: undefiend -> undefined
Fix more escalus_stanza.erl type discrepancies
Typespec escalus_connection
Fix more bugs with non-lists as #xmlel.children
Annotate escalus_app.erl
Annotate escalus_assert.erl
Annotate escalus_pred.erl

Touches escalus_utils.erl and exml.
Fix escalus_app:start/2 typespec
Fix escalus_pred/get_roster_items/1 typespec
Be more specific about stanza_type() usage in escalus_pred
Get rid of redundant case in escalus_connection
Redirect dialyzer output to dialyzer.log
Redo dialyzer integration in Makefile

Based on dialyzer rules from processone/ejabberd
with modified app list for erlang.plt.
Use exml 2.1.3 which doesn't make Dialyzer cry