Added "DSL Engineering: Designing, Implementing and Using Domain-Specific Languages"
Added "Naked objects"
Added "Methods and Techniques for the Design and Implementation of Domain-Specific Languages"
Added "Prolog Problems"
Added "S-99: Ninety-Nine Scala Problems"
Add Git Workflows
Merge pull request #625 from Mouseion/patch-gitbook

Add Git Workflows
Merge pull request #623 from alexanderfefelov/master

Added a few books
Merge pull request #624 from esparta/master

[es] added 3 books of Eugenia Bahit
[es] Adding node.js to the list.
Merge pull request #626 from matysanchez/master

[es] Adding node.js to the list.
[es] minimal fix & secondary link (a PDF) to 'Python para principantes'
Order list & add Functional Programming Section
[es] Fixing urls and adding 'Scrum & Extreme Programming (para programadores)'