Replace die('s with wp_die('s

[filosofo]

Latest revision; excluded ajax and wp-blog-header, as well as a few empty die()'s.

[ryan]

(In [3985]) Use wp_die(). Props filosofo. fixes #2914

[ryan]

I had to make a few changes. Don't wp_die after a redirect. Don't wp_die when wp-config cannot be loaded. Don't wp_die when an importer is using die as a means of sending non error output. A good general rule is to only wp_die when there is a die with a translatable string in it.

I remove a few wp_dies from wp-login in the reset/retrieve password areas. We could add these back if we integrate the echos that come before the die into the die.