update config: add requirements, add keywords, update --config descri…

…ption

src/agat/agat_sp_add_start_and_stop/config.vsh.yaml

@@ -5,7 +5,7 @@ description: |
   script looks at the nucleotide sequence and checks the presence of start
   and stop codons. The script works even if the start or stop codon are
   split over several CDS features.
-keywords: [gene annotations]
+keywords: [gene annotations, CDS, GFF]
 links:
   homepage: https://github.com/NBISweden/AGAT
   documentation: https://agat.readthedocs.io/en/latest/tools/agat_sp_add_start_and_stop.html
@@ -14,6 +14,8 @@ links:
 references: 
   doi: 10.5281/zenodo.3552717
 license: GPL-3.0
+requirements:
+  - commands: [agat]
 authors:
   - __merge__: /src/_authors/leila_paquay.yaml
     roles: [ author, maintainer ]
@@ -66,7 +68,7 @@ argument_groups:
       - name: --config
         alternatives: [-c]
         description: |
-          Input agat config file. By default AGAT takes as input agat_config.yaml file from the working directory if any, otherwise it takes the original agat_config.yaml shipped with AGAT. To get the agat_config.yaml locally type: `agat config --expose`. The `--config` option gives you the possibility to use your own AGAT config file (located elsewhere or named differently).
+          AGAT config file. By default AGAT takes the original agat_config.yaml shipped with AGAT. The `--config` option gives you the possibility to use your own AGAT config file (located elsewhere or named differently).
         type: file
         required: false
         example: custom_agat_config.yaml