Local modules and other changes

Administrator utilities
Improved media viewer
Enhanced "On this day" module
Changes log enhancement
Provide unified before/after display of changes
Shared notes shifted style from inline to css and added styles for
shared notes to all themes
reinstated custom js module - deleted module in error
Utility module fix bug that removed leading \ character in path
Utility module improve content of email message by using
WT_Mail::auditFooter
Implemented sitemaps
Added custom 404 file
Utility module bug fix - translations not working in cli mode
Take account of parent changes

If module has a constructor then ensure we call that of the parent .
Utility module: Simplified code now requires php 5.3 or greater. CLI
files must take the name of the module (by default 'utility'),
consequently, it's not necessary to pass the module name as a parameter
to the utility class constructor. Provided rudimentary validation of
parameters and updated help text to reflect that fact
tidy code