Defining nocorrect aliases only when ENABLE_CORRECTION is "true"

This commit move the nocorrect aliases definition so they're called
only when the user set ENABLE_CORRECTION to "true" to activate commands
autocorrection.

lib/correction.zsh

-alias man='nocorrect man'
-alias mv='nocorrect mv'
-alias mysql='nocorrect mysql'
-alias mkdir='nocorrect mkdir'
-alias gist='nocorrect gist'
-alias heroku='nocorrect heroku'
-alias ebuild='nocorrect ebuild'
-alias hpodder='nocorrect hpodder'
-alias sudo='nocorrect sudo'
-
 if [[ "$ENABLE_CORRECTION" == "true" ]]; then
+  alias man='nocorrect man'
+  alias mv='nocorrect mv'
+  alias mysql='nocorrect mysql'
+  alias mkdir='nocorrect mkdir'
+  alias gist='nocorrect gist'
+  alias heroku='nocorrect heroku'
+  alias ebuild='nocorrect ebuild'
+  alias hpodder='nocorrect hpodder'
+  alias sudo='nocorrect sudo'
+
   setopt correct_all
 fi