Merge pull request #107 from PaulBender/feature

Adds "Display posts in classic mode" option when editing user in Admin CP
IPv6 implementation

Fixed private.php
Fixes #1483 Large attachments, greater than PHP memory limit, fail
Fixes #2003 When replying to a subject that is at max character limit, you will get an error.
Fixing minor regressions
#2270 Minor Typo / Consistency Issue in showthread.php
Merge pull request #113 from JordanMussi/patch-3

#2270 Minor Typo / Consistency Issue in showthread.php
Add debug_summary to $templatelist
Improve consistency with square bracket language strings
Fix missing User CP language variable
Improve wording of "Empty Folders"

This makes it a little clearer what each column means.
Minor, correct two language strings
Update "Change x" forms

The Change Username/Email/Password forms are missing some table columns which results in a single centered textbox that looks out of place. This adds appropriate columns and changes the tcat wording for some forms.
Fix mobile detection in the ACP
IPv6 implementation
Fixes #111
IPv6 implementation
Updated comment
Custom Moderator Tools - Send PM

Added Send PM feature to Thread Tools (custom ones).
Also added send_pm(...) function to functions.php to facilitate sending
PMs by plugins.
Template group Admin Log support
This commit also fixes two minor bugs related to template group editing and deleting