Big refactoring.

* Don't override user defined styles
* Better modularisation of highlighters
* Allow to define which highlighters are activated
* Allow to define the order in which they are defined
* Minor performance optimizations
* Fixed some variables leak
* Improve documentation
* Brackets highlighter: use ZSH_HIGHLIGHT_STYLES instead of a specific array

highlighters/pattern/README.md

@@ -0,0 +1,21 @@
+zsh-syntax-highlighting / highlighters / pattern
+================================================
+
+This is the ***pattern*** highlighter, that highlights user defined patterns.
+
+
+How to activate it
+------------------
+To activate it, add it to `ZSH_HIGHLIGHT_HIGHLIGHTERS`:
+
+    ZSH_HIGHLIGHT_HIGHLIGHTERS=( [...] pattern)
+
+
+How to tweak it
+---------------
+To use this highlighter, associate patterns with styles in the `ZSH_HIGHLIGHT_PATTERNS` array, for example in `~/.zshrc`:
+
+    # To have commands starting with `rm -rf` in red:
+    ZSH_HIGHLIGHT_PATTERNS+=('rm -rf *' 'fg=white,bold,bg=red')
+
+The syntax for declaring styles is [documented here](http://zsh.sourceforge.net/Doc/Release/Zsh-Line-Editor.html#SEC135).