Move css into css file
Remove responsive css. This can be brought in after the apps have been converted.
cleanup
* Move header.php to template_top.php
* Code cleanup
* Move footer.php to template_bottom.php
* Code cleanup
Display left side navigation menu as a bootstrap nav list for the time being
Revert "Bootstrap Addition"

This reverts commit 76396ff996ec1e8bd01b59303c84c4d379fcabc5.
Simplified design update based on GLWalker
Merge branch '24' of https://github.com/haraldpdl/oscommerce2 into 24
Backport v3.0 customer class
* Use Bootstrap Buttons
* Remove jQuery UI usage
added alertBox class for messageBox output
make compatible with bootstrap alert messages

Conflicts:
	includes/classes/message_stack.php
Rename tep_ to osc_
Move the registered session_write_close shutdown function call to after other core classes have been initialized to allow other/earlier registered shutdown functions access to the session data
* Backport v3.0 MessageStack class
* Force use of addError(), addWarning(), addSuccess(), and addInfo() class methods instead of add()
Remove redundant file
Move payment error message to the messageStack
Remove redundant definitions
Replace jQuery UI Dialog with Bootstrap Modal