Rework trend and phenology charts on species pages

[burkmarr]

This is to replace the charts on the trends and phenology tabs of the species pages - using charts generated using the BRC charts library. The initial change is a like for like replacement of the current bitmaps with the data driven charts (created dynamically from data in CSVs).

The initial implementation can be trialed on this Pantheon multidev site: https://burkmar-brc-ukbms.pantheonsite.io/species

[DavidRoy]

We would like the new charts to go live to co-incide with the official release of the 2022 results on Friday 24th March
@burkmarr - is that ok from your side
@colinharrower - can you provide the necessary datasets in time

[burkmarr]

@DavidRoy - that should be fine.