Allow for missing oik-loader-extras.csv

[bobbingwide]

In sb/oikcom I decided to activate oik-loader logic.
I got the following messages when trying to rebuild the index.

Warning: file(C:\apache\htdocs\oikcom/wp-content/mu-plugins/oik-loader-extras.csv): 
failed to open stream: No such file or directory in 
C:\apache\htdocs\wordpress\wp-content\plugins\oik-loader\includes\oik-loader-extras.php 
on line 26

Warning: Invalid argument supplied for foreach() in 
C:\apache\htdocs\wordpress\wp-content\plugins\oik-loader\includes\oik-loader-extras.php 
on line 9

Workaround

Create an empty file