mythrename needs -b when using file command

[asmythtv@…]

When you use the file command to dectect what sort of file you are working with you need to use the -b option of file. If you don't then file will preface the result with the file name.

So if the file is called: a.mpg, and it's a text file it will say: a.mpg: ASCII text

Then when you do the regex to check if it has mpg in the result - it will always succeed! (Because the file name has the word .mpg in it.)

Anyway use -b and file will not echo the filename.

[danielk]

(In [7518]) Fixes #441.