added History.php

added beginning workings of history.php that successfully calls the
database and returns the table entries
display History properly in table form

Used ajax to call the function returnHistory that displays all current
entries at this point in a table format. The function returnHistory
returns a string of HTML code that displays the data in a table. Things
that need to be done include:

-getting a CSS template to make the table look pretty
-sorting options
-editing options
-having the entries only display ones that belong to the user