Make description an optional field

Why?
When I was uploading archives to Glacier I didn't like I had to enter the description of the archive because it's file name was unique in our system anyway. Using the file name as a descriptor would therefore be very useful. I already wrote a script which did this, but is felt like a hack.
Since I assumed may be more people felt this way, I wanted to fix it.

How?
I modified the program to include a method addOptionalParameter and made description optional. In case description is omitted, it will receive a default value when uploading which in turn depends on the file name you are trying to upload.

Result:
In case the description option is omitted, the file name without the directory name is used as a description.