adapt feature names

[wgiese]

remove:

flow_shape_alignment, flow_shape_alignment_nuc, vec_X, vec_Y, flow_alignment, maker_vec_norm

rename:

X_nuc -> nuc_X etc.

golgi apparatus -> organelle features

distance -> organelle_distance, angle_rad -> organelle_orientation_rad, angle_deg -> organelle_orientation_deg

marker features mean_expression -> marker_mean_expr, sum_expression -> marker_sum_expr , X_weighted -> marker_centroid_X, Y_weighted -> marker_centroid_Y, marker_polarity_rad -> marker_centroid_orientation_rad, marker_polarity_deg -> marker_centroid_orientation_deg mean_expression_mem -> marker_mean_expression_mem, sum_expression_mem -> marker_sum_expression_mem mean_expression_nuc -> marker_mean_expression_nuc, sum_expression_nuc -> marker_sum_expression_nuc mean_expression_cyt -> marker_mean_expression_cyt, sum_expression_cyt -> marker_sum_expression_cyt

Add: orientation 1. marker versus nucleus and 2. nucleus displacement.

1. vector (X_nuc,Y_nuc) -> (X_weighted,Y_weighted) marker_nucleus_orientation_rad, ... (marker feature if nucleus given)
2. vector (X_cell,Y_cell) -> (X_nuc,Y_nuc) nucleus_displacement_orientation_rad, ... (nucleus feature)

abbreviations: nucleus = nuc, expression = expr