Fixed inputs of data info display, float display and instance transform modulator and removed reduntant connection_changed() methods.
Fixed inputs of the cos, delta, divide, equals and exp plugins.
Fixed inputs of the flat shader plugin and removed redundant connection_changed() method.
Fixed inputs of the from mesh / ... custom shader plugin and revised their connection_changed() methods.
Fixed the inputs of the format string, graph, if and if else plugins.
Fixed the inputs of the get matrix plugin and removed empty connection_changed() - this behaviour is no longer supported.
Fixed the input of the instance array / cube plugins and updated them to gracefully handle a null mesh.
Renderer: Added default value for a null vector: [0, 0, 0].