Merge pull request UNFmontreal#268 from SamGuay/tuto-parallel

[DOC] - Tutorial on parallel x dcm2bids

Author: arnaudbore

docs/tutorial/index.md

@@ -9,6 +9,8 @@ commands.
 
 [First steps with dcm2bids](first-steps.md){ .md-button .md-button--primary }
 
+[Convert multiple participants in parallel](parallel.md){ .md-button .md-button--primary }
+
 ---
 
 !!! tldr "Interested in co-developing a tutorial?"