[development] Require external files from module.install

[Cameron B. Prince]

Hi Christoph,

>> When the module is enabled via drush the contents of each file are printed
>> to the screen
> 
> Have you made sure your included files begin with '<?php'? It sounds as
> though your included code is printed instead of executed, which happens
> when there are no enclosing PHP tags.

This was it! I should have caught it, but I guess this goes to prove brain
cramps happen when coding at 3AM.

Thanks for your help,
Cameron