Revolt Plugin Refactored

[caronc]

Description:

Related issue (if applicable): #1057

Refactored the Revolt plugin to allow markdown to work. Refactoring also allows multiple channels to be specified on the Apprise URL:

• revolt://bot_token/channel
• revolt://bot_token/channel1/channel2/channelN

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• No lint errors (use flake8)
• 100% test coverage

Testing

Anyone can help test this source code as follows:

# Create a virtual environment to work in as follows:
python3 -m venv apprise

# Change into our new directory
cd apprise

# Activate our virtual environment
source bin/activate

# Install the branch
pip install git+https://github.com/caronc/apprise.git@1057-revolt-tidy

# Test out the changes with the following command:
apprise -t "Test Title" -b "Test Message" \
  "revolt://credentials

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (6764590) 99.26% compared to head (6523e20) 99.27%.

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1062      +/-   ##
==========================================
+ Coverage   99.26%   99.27%   +0.01%     
==========================================
  Files         136      136              
  Lines       17733    17738       +5     
  Branches     3616     3618       +2     
==========================================
+ Hits        17602    17610       +8     
+ Misses        120      119       -1     
+ Partials       11        9       -2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.