Update fep-class.php

I was looking to customize a few areas of the plugin so was looking for filters/actions to plug into. I have rewritten the function dispMenu to include some filters for changing the label text for each of the buttons:

fep_newmessage_label
fep_messagebox_label
fep_contactmessages_label
fep_announcements_label
fep_directory_label
fep_settings_label
fep_viewallmessages_label
fep_viewallcontactmessages_label
fep_spam_label
fep_newemail_label

In addition, I have created two filters to amend the html generated for the beginning and end sections of the menu area:

fep_menu_open
fep_menu_open

I have also added a filter to enable styling of the buttons themselves:

fep_menu_button

This also allows the insertion of a css class for further styling if needed.