Work towards #56: Splitting up the README

I did the job and splitted up the readme, hopefully everything was
splitted correctly...

idioms/index.md

@@ -0,0 +1,24 @@
+---
+layout: pattern
+title: Idioms
+folder: idioms
+categories: pattern_cat
+tags: pattern_tag
+---
+
+
+A programming idiom is a means of expressing a recurring construct in one or
+more programming languages. Generally speaking, a programming idiom is an
+expression of a simple task, algorithm, or data structure that is not a built-in
+feature in the programming language being used, or, conversely, the use of an
+unusual or notable feature that is built into a programming language. What
+distinguishes idioms from patterns is generally the size, the idioms tend to be
+something small while the patterns are larger.
+
+* [Execute Around](#execute-around)
+* [Poison Pill](#poison-pill)
+* [Callback](#callback)
+* [Lazy Loading](#lazy-loading)
+* [Double Dispatch](#double-dispatch)
+* [Resource Acquisition Is Initialization](#resource-acquisition-is-initialization)
+* [Private Class Data](#private-class-data)