v0.4.0: Towards 1.0

Many improvements and feature extensions to reach 1.0 milestone:

• Support newer python-acme releases
• handling nonce errors (with updated acme library), fixes #8
• switch to ACME v2 endpoints
• support for wildcard domains
• a basic logging framework, fixes #3
• test against multiple ACME backends (boulder and pebble)
• use docker-compose for simple and reliable ACME backend setup
• Refresh supported Python versions (add new released major versions,
  drop unsupported old ones): target 3.5 to 3.8 for now
• Dedicated HTTP error codes for rating limiting and validation errors
• Simplified Python dependencies: only use PyOpenSSL and cryptograph to
  parse CSR and during tests

v0.3.1: Bugfixes around `dns01-dnsUpdate`

Multiple bug fixes:

• Fix auth-block specific storage and verification settings
• IOError when replace certification in file storage
• Fix typos in dns01-dnsUpdate verification

v0.3.0: DNS01-support

Basic future set for DNS01-challenge support - #7

v0.2.0: Reaching 1.0 core features implention

Reaching base architecture for 1.0 release. This includes:

• Restucture code and! config to support multiple verification mechanism
• WIP: experiment / prepare for dns01 challenge support (via dns updates)
• add storage support to not reissue CSRs the same pem, supporting reissue from multiple machines via a once shared key and CSR
• support newer python-acme releases