Translate functions "usage_text"

[farmio]

• Translate functions "usage_text".
• Refactor knx_master.xml loader slightly for better readability.
• Add functions project to refresh_stubs helper script. (2nd commit - see only 277dfc6 for better diff since the helper reordered the stub)

cc @bacherd

[codecov]

Codecov Report

Merging #262 (7d3208a) into main (4011b76) will decrease coverage by 0.27%.
The diff coverage is 89.65%.

@@            Coverage Diff             @@
##             main     #262      +/-   ##
==========================================
- Coverage   97.61%   97.34%   -0.27%     
==========================================
  Files          21       21              
  Lines         923      943      +20     
==========================================
+ Hits          901      918      +17     
- Misses         22       25       +3     

Files Changed	Coverage Δ
xknxproject/models/__init__.py	100.00% <ø> (ø)
xknxproject/models/models.py	98.06% <86.36%> (-1.40%)	⬇️
xknxproject/loader/knx_master_loader.py	97.87% <100.00%> (-0.05%)	⬇️
xknxproject/loader/project_loader.py	98.05% <100.00%> (ø)
xknxproject/xml/parser.py	93.47% <100.00%> (ø)