Support explicit definition for 1D plots

This MR allows to define 1D plots explicitly in the scan info (as it was possible with curve and scatters).

This is dedicated plot for 1D data (like spectrum, profile ROIs from Lima, or data manually published in BLISS scan sequences)

• The ScanInfo provides now a add_1d_plot (like there was a add_scatter_plot)
• This plot is read by Flint to display a dedicated widget
• Flint one dim widget was updated to provide the same toolbar as other widgets + retrieve/restore of user selection
• Plus few fixes on the remote API