pypima/pima.py: Add Pima.acta() method.
bin/test.py: Add pima.acta() for testing.
pypima/db.py: fri2db(): write `scan_name` to the

database.
pypima/pima.py: Add `acta_plot` function.
pypima/raexperiment.py: Add generate_autospectra()

method.
bin/test.py: Test for generate_autospectra().
pypima/pima.py: acta_plot(): Fix command line.
pypima/raexperiment.py: generate_autospectra():

Use temporary directory for plots.
bin/pima_auto.py: Add autospectra generation.