Packet feedback 2024 08 12 and general packet additions

[sthagen]

• [x] corrected offset calculations in connect packet
• [x] harmonized the parameter for offset notation in commented packets
• [x] increased the font in disconnect flags section for readability
• [x] added diagrams for general packet parts
• [x] removed directory with few alternate example diagram formats to reduce distractions

[lenzarda]

Connect packet:

• I think S should be =R+3+L to be consistent with the above field (as R=P+1)
• I think U should be =S+N to be consistent with the above field (as T=S+1)