Update free-programming-books-zh.md
Merge pull request #1111 from gmszone/patch-1

Update free-programming-books-zh.md
Added books in slovak language
Added czech book for security
Update URL to czech books

Change URL to official source
Added author for czech books
Merge pull request #1112 from grogy/slovak-books

Added books in slovak language
Merge pull request #1113 from grogy/czech-books

Added czech book for security
Merge branch 'czech-books-update' of github.com:grogy/free-programming-books into grogy-czech-books-update

Conflicts:
	free-programming-books-cs.md
Merge branch 'grogy-czech-books-update'
add The Django Book 2.0 to Python series
Merge pull request #1115 from LeonSin/master

add The Django Book 2.0 to Python series
added two Git resources; adjusted some format details
Merge pull request #1116 from sunxb10/master

added two Git resources and adjusted some format details
un livre à prix libre sur Vim
Merge pull request #1117 from maieul/master

un livre à prix libre sur Vim