SMF Increase Personal Text Limit 1.0

This tiny mod just raises the personal text character limit roof from 50 characters to 5,000. Only makes one change, no biggie. It will install perfectly fine on both SMF 2.0.x and 2.1+, there are install handlers for both, and shouldn't conflict with anything. Note that if you want to later go back to the 50 character limit, those with longer personal texts/blurbs will retain those longer texts until they edit and save their profile again.