Revamp to metadata

[lukestroh]

Consider a revised metadata structure to keep everything in one file and providing more information so that users only have to look in one place.

{
    namespace: <namespace>,
    tree_id: <tree_id>,
    tree_type: <tree_type>,
    seed: <seed>,
    config_params: {
        spur: {
            max_length: <max_length>,
            growth_length: <growth_length>,
            ...etc.,
        },
        branch: {<branch_config>},
        ...etc.,
    },
    semantic_data: {<semantic_data>},
    instance_data: {<instance_data>},
    cylinder_data: {<cylinder_data>},
    tree_hierarchy: {<tree_hierarchy>},
    <anything else you think a user may want to have for future analysis. How might they want to analyze groupings of trees? Types of branches? etc.>
}

[lukestroh]

Limb name ID numbers should reset for each tree. I shouldn't expect to see a "Trunk_20" in the 19th tree that I generated. See pic for example.

[lukestroh]

#14 adds hierarchy, cylinder color data. Still needs semantic and instance data.