Added more packages and reorganised the YAML files
This merge restructures the YAML files to make them a little easier to read, and adds some new packages:
- reorganised YAML files into build tools, python tools, and lscsoft packages,
- added some common build tools (compilers, cmake etc);
- added python tools (linters)
compilers metapackage is now available on
conda-forge, so I have added that.