Merge pull request #281 from jburns131/checkCoreUpdates

Check core updates
Closes #283 whitelist <script> attributes and noscript tag (when script posting is enabled)
Issue #283 target attribute is valid in html5
Display upgrade alert on main admin page only.
Clean up of menu installs.
Menu news_months_menu has 2 entries.
One was set to location that conflicted with Login Menu.
Both using location 1, Order 1.
Changes;
Removed unneeded news_months_menu
Set other one to location 1, order 2 to remove conflict.
Tested - Viewed DB after install - was OK.
Improved logging of the upgrade process.
Fixes issues with menu munipulation.
1. Scans all Menu's, All locations, And reorders them properly.
- Does all in case a menu was deleted from system, but active in another area.
2. When activating. Increments so proper order number is assigned.
3. Fixed deactivating. It properly reorders remaining menus
- And removes duplicates, if a loc-0, order-0 exists.
- Also gives Admin log info - Menu Name, Last Location, Last Order. MenuID
Call to menuScanMenus() Not needed.
It's already called by menuModify() in menumanager_class.php
So it runs 2x on each page load.
Code cleanup on usertheme_menu. Very outdated.
Some userclass fields didn't support class ID>255, visibility needs to support 'not member of...'. Possible tenuous link to Issue #266
Issue #268 - graceful retreat if CURL not installed on getRemoteFile()
Fixes Issue #266 item 4
Closes #287 - enhancement to already logged in message.
Issue 268 - correct error logging message
#268 - Added cURL check to remote themes/plugins download
Issue #268 Syntax error in last commit.
Chart class added.
InfoPanel using new chart class. Work in progress to convert stats plugin data to use it.
Merge pull request #290 from BillyBoy0823/master

Closes #251 and Closes #141 - Clean up of menus install
Notes and TODO added.