Better wording

Refomulated for better understanding
Merge pull request #510 from gibas/07-customizing-git

[pl] next part of chapter 7
[th] Retranslate README file
Rename README to README.md

Fix document not render in GitHub
Merge pull request #511 from Reizinixc/th

[th] Retranslate README file
nl: Fixed some typo's in chapter 8
nl: Chapter 8: Made some sentences more fluent.
Merge pull request #512 from Jopie64/master

Some changes in the Dutch translation
Fixed a few obvious spelling, grammar, punctuation and capitalization errors in the branching
chapter of the German translation.
Merge pull request #513 from Brackmeister/master

Some fixes to the German translation
Second version of the patch (беспорядок => путаница)
Merge pull request #504 from tendium/patch-1

Better wording
Fix typo. trços -> traços.
Merge pull request #516 from deniscostadsc/master

Fix typo. trços -> traços.
Correct stylistic issues in Russian translation
Merge pull request #517 from GArik/RU

Correct some parts in Russian translation v2
fix duplicated typo "...fez o rebase do seu do seu trabalho..."
Merge pull request #519 from masakik/patch-1

fix duplicated typo "...fez o rebase do seu do seu trabalho..."
[zh] fix branch name half translate to chinese
[ko] translation update

[ko] translation update ch1 to ch4

[ko] translation update ch5

[ko] translation update ch6

[ko] translation update ch7

[ko] translation update ch8

[ko] translation update ch9

[ko] proofreading.

[ko] fix mistyping.