Add the disable in nodes policy for more accuracy in directed graph

[ta99i]

modified:   lntopo/parser.py
modified:   lntopo/timemachine.py

Added the disable attribute to the nodes policy data structure.
    The disable parameter is derived from the channel_flags field, specifically using bit position 1, as described in the BOLT 7 specification.
    This change allows for better representation of disabled or inactive channels in the directed graph, ensuring that the graph accurately reflects real-time network conditions.