Reviewing "Commit Guidelines"

commit è femminile
Reviewed "Commit Guidelines"
Update 01-chapter1.markdown
Merge pull request #634 from gmaghera/master

Update 01-chapter1.markdown
Fixed "Hosted Git" Title

In italiano usiamo "hosting" o "host"
Merge pull request #635 from daftano/master

[it] update chapter 4 and 5