Refine timeline display using plotly/Dash

[andrewphilipsmith]

• [x] Add adjustable timeline radius around CMOC points
• [x] Add a control for the timeline radius
• [x] Translucent Radius for CMOC
• [x] Group controls for CMOC on/off, Point on/off, Radius on/off
• [x] Remove default plotly controls in top right
• [x] Change default visibility of different CMOC methods
• [x] Add human friendly names of CMOC methods
• [x] Change colours for different CMOC
• [x] Change y-axis labels
• [x] Change width of timeline plot area
• [x] Prevent the user from changing the visibility of the timeline itself (only the CMOCs)

[andrewphilipsmith]

For I have implemented a simple workaround for "human friendly names of CMOC methods", which is to apply Title Case and replace _ or - with a space. I've added a note to incorporate a more complete solution in #32.

[andrewphilipsmith]

For now, I have applied a fixed width to the timeline plot. This is not a satisfactory solution. This needs to be addressed in #49