Use logger exceptions than debugs to show errors

[sherlockwisdom]

Please comb through the code and replace the loggers using debugs in exceptions to logger.exception instead. Sample debug usage that needs change below:

SMSWithoutBorders-customplatform-Slack/slack.py

Line 40 in 6efc147

logger.debug("- Error posting message: %s", err)

[Idadelveloper]

@sherlockwisdom done