[2pt,1pt] Design the UX for selecting signals

[RalphSteinhagen]

As the number of signals is very large (100k++), a UX needs to be designed
to allow easier searchin of the signals based on:

• signal name
• signal type (voltage, current, pressure
• signal properties (sample rate, unit, ...)
• data type (time-domain, spectra, ...)
• device
• device category (e.g. power converter, beam position monitor, cavity, magnet, cooling water, ...)
• machine/accelerator where the device is located
• ...
  The UX needs to accommodate different users' needs and priorities

-- it should not be focussed only on a specific /path/ for
selecting signals.

Implementation of the new UX will be a separate task.

See also UX Meeting in Belgrade #99

[ivan-cukic]

Changes to the above:

• combo boxes above the search bar
• active filters should be shown outside of the search bar (in the next line)
• active filters should also be highlighted by having the active combobox visually distinct (it is already like that in the mockup, but it is subtle and easily missed)
• accelerator and experiments selectors should be merged into one called Domain

[ivan-cukic]