Cosmetic changes in main.sh

Ciao Domenico, these look like very many changes in the file, but actually it's a simple tidying up of tabs and empty spaces (look at the detailed logs of the three commits). I file this as a separate MR for clarity, but can you please approve it relatively quickly? Thanks Andrea

mentioned in commit 0d57f1e8

By Domenico Giordano on 2019-02-05T22:52:44 (imported from GitLab project)

merged

By Domenico Giordano on 2019-02-05T22:52:44 (imported from GitLab project)