Spots initially loaded from loc file, are now active for another acquisition.

Previously, the saved spots were only displayed, but not active items for
acquisition.

Fixes: issue #24.

Signed-off-by: Nicola Ferralis <feranick@hotmail.com>
Save spot location file now indicates the energy in the filename

Signed-off-by: Nicola Ferralis <feranick@hotmail.com>
Save spot location filename includes energy of first image not last.

Signed-off-by: Nicola Ferralis <feranick@hotmail.com>