Fix several wrong linkages

A number of changes were done to fix issues arising in the build of the user guide.

Several links were broken or not updated.

A conda environment with the required set of packages was create to help out users.

source/global.rst

@@ -57,7 +57,7 @@
 
 .. _EGU: http://www.egu.eu
 .. _Special Issue: https://www.geosci-model-dev.net/special_issue40.html
-.. _BFM man: https://cmcc-foundation.github.io/www.bfm-community.eu/files/bfm-nemo-manual_r1.0_201508.pdf
+.. _BFM man: https://bfm-community.github.io/www.bfm-community.eu/files/bfm-nemo-manual_r1.1_202006.pdf
 .. _RST man: https://www.sphinx-doc.org/en/master/usage/restructuredtext/index.html
 .. _PAPA station: http://www.pmel.noaa.gov/OCS/Papa/index-Papa.shtml
 .. _sette inputs: https://gws-access.jasmin.ac.uk/public/nemo/sette_inputs