GitLab

- Rename function since it supports both line and column charts

- Add logic for comparing the lengths of the timestamps and aggregated
values arrays

- Update the function documentation

- Move the function to a different module file

... based on selected drop-dowwn options

Confirm that the selected drop-dowwn options are valid before fetching
the observations

Function uses options from drop-down list that have been selected by a
user to populate the appropriate observations and then draw the
appropriate chart