fix `reqOptions` usage.
fix `reqOptions` usage.

thanks to:
- https://github.com/matthiaskomarek/nodejs-ebay-api/commit/c7e89ec2633ac1acf62af82c0d3c63db3697a28c
- https://github.com/afreeland/nodejs-ebay-api/commit/1281b079a7cfbe49eafa2bdb1ababa8ef3040972

fixed issue benbuckman#15

also remove overloaded and unnecessary `var request`.

benbuckman/nodejs-ebay-api