Py plot: correct vertical extension of color legend

Too high in rectangular images, should align with vertical extension of main frame.

added Python label

added peripheral label

created merge request !248 (closed) to address this issue

mentioned in merge request !248 (closed)

changed title from Py plot: fix colorbar to Py plot: correct vertical extension of color legend

changed the description

mentioned in merge request !374 (merged)

Resolved in !374 (merged)

closed