tune up bingo.py

**Random:**
* make shebang more 'dynamic'
* made main() function
* works with python 3 as far as I can see (can't guarantee it works with 3) 

**Mods:**
* create width_type() to catch width-less-than-0 edge case
* tune up argeparse statements
* mod -f functionality for no-flag/flag-no-arg/flag-plus-arg cases
    * no flag = stdin
    * flag-no-arg = bing.list in current working dir
    * flag+arg = file is arg
* repace getFile() function with a with statement

**Bugs:**
And you don't *need* to use -w flag (it failed to default to value 9, the nargs in arparse creates a list)