WLED Upgrade improvements

[frenck]

Proposed Changes

More enhancements to the WLED Upgrade methods.

• Extended upgrade.py example
• Introduced and used a WLEDUpgradeError
• Don't upgrade if the version matches the already installed version
• Don't upgrade if the existing version is unknown
• Add support for ESP32 based Ethernet boards (thanks Aircoookie for the hints on that one!)

[codecov]

Codecov Report

Merging #468 (50f5172) into main (2f85409) will decrease coverage by 0.66%.
The diff coverage is 7.69%.

@@            Coverage Diff             @@
##             main     #468      +/-   ##
==========================================
- Coverage   57.80%   57.14%   -0.67%     
==========================================
  Files           4        4              
  Lines         538      546       +8     
  Branches      116      119       +3     
==========================================
+ Hits          311      312       +1     
- Misses        207      214       +7     
  Partials       20       20              

Impacted Files	Coverage Δ
src/wled/__init__.py	100.00% <ø> (ø)
src/wled/wled.py	41.00% <0.00%> (-1.06%)	⬇️
src/wled/exceptions.py	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2f85409...50f5172. Read the comment docs.