Finished slideshow

Added the client slideshow, moved files into includes, added about.
Added Change Password

Added the change username/password functionality, fixed the salts, and
added a time limit to sessions.
Fixed 20-files-at-a-time problem.

php.ini had no "max_file_uploads" directive. Added it, set it to 250.
Also put in UI elements that specify the limit.
Input Validation

Disabled the ability to submit image upload in the event that >250
images have been selected.