Add gfa, irb utility_belt, and gitignore DS_Store and .svn

.gitignore_global

@@ -1,3 +1,5 @@
+.DS_Store
+.svn
 *.swp
 *.swo
 doc/tags*

.irbrc

@@ -1,3 +1,4 @@
 require 'rubygems'
 require 'interactive_editor'
+require 'utility_belt'
 

.zprofile

@@ -244,6 +244,7 @@ alias gd="git diff"
 alias gdc="git diff --cached"
 alias gc="git commit"
 alias gca="git commit --amend"
+alias gfa="git fetch --all"
 alias gr="git remote -v show"
 alias gp="git push"
 alias gu="git pull"