Make GPS Lk/Unlk and GPS Clock Power to plot in the same channel

closes #162 (closed), #142 (closed)

• Collect GPS Clock Power under channel GPS Lk/Unlk with value 0
• In plot_line_dots, if the channel is GPS Lk/Unlk, plot all value=0 in a separate plot() with color in the database as Z:color
• Remove linkedChan related code from all files and database.

DELETE FROM Channels WHERE channel="GPS Clock Power";
DELETE FROM Parameters WHERE param="GPS Clock Power";
UPDATE Parameters SET valueColorsB='L:W|D:W|Z:C', valueColorsW='L:W|D:W|Z:C' WHERE param='GPS Lock/Unlock';