Moved PHP files to "lib" folder
Moved Javascript files to "lib" folder
Moved login page inline CSS to "login.css"
Moved database functions to class "Database"
Removed the html template, compensated with a direct HTML code inside PHP "else" statement
Moved database function in class "Database";
Corrected database-using webpages accordingly;
Moved config file from PHP to JSON with more config variables;
Corrected login page redirection on wrong username or password.
