Add Introducción a Rails to the list of spanish books.

This book is a spanish translation of the official guide "Getting Started
with Rails."
Merge pull request #1003 from jbranchaud/add-intro-a-rails

Add Introducción a Rails to the list of spanish books.
add TLA book by Leslie Lamport
add the index for TLA
Merge pull request #1004 from AndriyLin/master

[init] - TLA
Add Groovy/Gradle/Grails documents in Japanese.
Merge pull request #1006 from sudoyu/patch-1

Add Groovy/Gradle/Grails documents in Japanese.