Add IP-Secure tunnelling support

[farmio]

Description

Add IP-Secure tunnelling support.

This is work in progress:

• add necessary Frame parsers
• add parsing and decryption of knxkeys files
• verify knxkeys file with signature before using it
• add SearchRequestExtended support to check for available tunnel users
• add configuration options for needed parameters (passwords / keys / files)
• add SecureSession class (between Interface and Transport)
• SecureSession
  • properly initiate handshake and authentication
  • keep it alive
• decrypt, verify and handle various encrypted KNXnet/IP frames
• properly react to various SessionStatus indications
• properly reconnect on lost TCP connection (bubble up connection_lost to Tunnel)
• add tests... lots of tests

Fixes # (issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• I have performed a self-review of my own code
• The documentation has been adjusted accordingly
• The changes generate no new warnings
• Tests have been added that prove the fix is effective or that the feature works
• The changes are documented in the changelog
• The Homeassistant plugin has been adjusted in case of new config options

[codecov]

Codecov Report

Merging #879 (5b19f24) into main (7542d97) will increase coverage by 0.11%.
The diff coverage is 95.13%.

@@            Coverage Diff             @@
##             main     #879      +/-   ##
==========================================
+ Coverage   95.50%   95.61%   +0.11%     
==========================================
  Files         116      128      +12     
  Lines        7008     7670     +662     
==========================================
+ Hits         6693     7334     +641     
- Misses        315      336      +21     

Impacted Files	Coverage Δ
xknx/exceptions/__init__.py	100.00% <ø> (ø)
xknx/io/transport/tcp_transport.py	46.03% <33.33%> (-1.34%)	⬇️
xknx/io/tunnel.py	75.84% <71.05%> (+1.62%)	⬆️
xknx/knxip/session_status.py	84.00% <84.00%> (ø)
xknx/io/connection.py	97.05% <90.90%> (-2.95%)	⬇️
xknx/knxip/session_authenticate.py	91.66% <91.66%> (ø)
xknx/knxip/session_request.py	92.00% <92.00%> (ø)
xknx/knxip/session_response.py	92.30% <92.30%> (ø)
xknx/io/secure_session.py	96.37% <96.37%> (ø)
xknx/knxip/secure_wrapper.py	97.14% <97.14%> (ø)
... and 17 more

[marvin-w]

Updates black in order to fix CI error: psf/black#2966