Add a Glossary

[asmacdo]

The website subcommittee identified a need for a glossary on the new site. Lets start collecting terms that might be useful here. We can trim down at implementation

ReproNim
ReproLake
ReproPond
Reproducibility
Re-execution
ReproCenter
BIDS
BIDS-app
DICOM
Nifti
Container
Docker
Podman
Singularity
FAIR
provenance
NIDM