Add tutorial: GC-MS analysis with apLCMS [metabolomics]

[xtrojak]

Add a new tutorial to the metabolomics category. The tutorial explains how to use apLCMS (resp. a forked version recetox-aplcms) for analysis of GC-MS data.

TODO:

• Content
  • add a hint on how to select a single file from the collection as input for a tool
  • explain more the outputs of align features, compare with pre-recovered data
  • improve introduction
  • add conclusions & resulting data
  • fill in objectives & key points
  • add missing questions
• Figures
  • figure describing gaps in the feature table GTN rcx-aplcms: create picture illustrating weak signal RECETOX/training-material#9
  • figure depicting median m/z and retention time values for a group of aligned features
• Data and workflow
  • updated the workflow with suitable parameter values to work with the training dataset
  • describe the known table and add a zenodo link* to it
• Optional
  • update GC-MS tutorial with XCMS with the possibility into to use recetox-aplcms for the peak detection instead of XCMS + include zenodo link (* can be the same one) to pre-computed data