added setTimestamp to DateTime functions, accounts for null timestamp, added numerous sort functions

solves timestamp problem if validate_timestamp is disabled.
the sorting functions are needed for sorting the cached scripts
Added two functions for new cached scripts layout

get and set position for highlighting files within directory
modified to work with rewrite/$_GET. Added sorting to directories

Invalidate button will work with either rewrite or $_GET options.
I have added the ability to sort by directory, memory, hits or files.
The files in each directory are displayed by name ascending.
Modified to work with both rewrite/$_GET. Added ability to handle sort parameter

Will work with rewrite or $_GET. Strips off sorting parameter if using
rewrite
Added cached scripts headers and updated config options to mirror OpCache official descriptions

New scripts values are needed for the cached scripts sorting
Modified reset button to work with both rewrite and $_GET

Really only need if you want to use $_GET instead of rewrite
Modified and added rules for cached scripts layout

Needed for sorted cached scripts
Added constant useRW in bootstrap. Modified page.phtml to use 'usrRW'

useRW = true then use ReWrite , false then use $_GET.
page.phtml  uses value to set anchors
Minor changes to use constant useRW

if useRW is true sort parameters are passed on end of 'cached-scripts'
as 'cached-scripts_sp' instead of using 'cached-scripts?s=sp'.
Optimize sort functions

Status.php -
Optimized sorting functions,
Added $ValidTimestamp for display of `created time`
Added anchor function to create header sort anchors.
Added populateDirectories function to fill directories array

cached.phtml -
Updated to utilize new functions added to Status.php
Merge pull request #1 from k9krew/master

Some commits from k9krew