Keep content of messages if context is unencrypted

Fixes #65
Handle incoming irc ACTION in unencrypted message
Update tests for `html_escape` policy

The policy is only applied if we are actually in an encrypted context
Merge pull request #72 from tribut/logging-reset-default

Reset logging to default if no explicit value was set
Add SessionTestCase class for session tests.
Add infolist to WeeChat mock.

Also add commands and config_integer_default.
Add tests for log level restoration.
Add name and plugin to mock buffers.
Use buffer_get_string in get_logger_option_name.

Wrapper handles encoding.
Check for unset log level first in get_log_level.

Avoid searching infolist if possible.
Remove empty line.
Merge pull request #73 from tribut/modify-messages-unencrypted

Only modify message contents if the context is encrypted
Revert "Update tests for `html_escape` policy"

This reverts commit 0e04ebf6f5232bc305d28ab30a08ec3ae39667cb.
Tests for msg_convert_in/out when not encrypted.

Unit tests for #73.
Merge pull request #74 from tribut/unencrypted_action

Handle incoming irc ACTION in unencrypted message
Test for IRC ACTION in unencrypted message.
Remove default log level from message