Editing 01-chapter6.markdown

To update rebase message with new output
Merge pull request #729 from daftano/en

Editing 01-chapter6.markdown
Merge pull request #728 from daftano/master

[it] update chapter 2
[it] Reviewed chapter2

Reviewed "Limiting Log Output"
[it] Reviewing chapter2

Reviewed "Using a GUI to Visualize History"
[it] chapter6

Translated "Issues with Submodules"
[it] chapter6

Cosmetic review