Add a bash book:  Conquering the Command Line
Merge pull request #799 from HungMingWu/master

Add a bash book:  Conquering the Command Line
Merge pull request #800 from esparta/master

[es] New section (& book): Erlang
Adding Code Guide to HTML/CSS section.
Merge pull request #801 from jbranchaud/adding-html-css-resource

Adding Code Guide to HTML/CSS section.
Add a single haskell book
Merge pull request #802 from vikt0rs/master

Add one more book about haskell
[es] Adding Erlang book