Added a bibtex file for references and started more work on the text.

Found a bug in the pollen data that may cause problems down the line, there is only AbiesEast in the dataset, no AbiesWest or Abies undiff.  This might mean that I need to re-run everything again.
Found a bug in the codeing of pollen taxa that excludes western Abies from pollen assemblages, effectively changing the assemblages.  Re-ran the analysis using only eastern sample sites.
Merge branch 'master' of https://github.com/SimonGoring/NoAnalogueError