v2.1.1

This is a patch release

Bug fixed:

• #841 infinite loop when using domains ending or starting with a dot (#842)

Dependencies:

• acme.sh -> 2.9.0
• dockergen -> 0.8.0
• golang -> 1.17.4-alpine
• alpine -> 3.15.0

Other changes:

• Documentation updates (#790, #857, #875)
• Fixes to the test suite (#899)