Split all the e2e tests in their own files

Some duplication is avoided, but most importantly: it’s much much cleaner,
easier to find, functions have been cleaned up (functools.partial usages are
now hidden), etc.

tests/end_to_end/scenarios/raw_message.py

@@ -0,0 +1,13 @@
+from scenarios import *
+
+scenario = (
+    sequences.handshake(),
+    send_stanza("<presence from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}/{nick_one}' />"),
+    sequences.connection("irc.localhost", '{jid_one}/{resource_one}'),
+    expect_stanza("/message"),
+    expect_stanza("/presence"),
+    expect_stanza("/message"),
+
+    send_stanza("<message from='{jid_one}/{resource_one}' to='{irc_server_one}' type='chat'><body>WHOIS {nick_one}</body></message>"),
+    expect_stanza("/message[@from='{irc_server_one}'][@type='chat']/body[text()='irc.localhost: {nick_one} ~{nick_one} localhost * {nick_one}']"),
+)