Add option to output fieldnames as headers

Adds a new -j option which outputs the query field names as the
headers of the output. Defaults to off to keep the old behaviour.
Merge branch 'master' of https://github.com/theomega/q
Replaced clumsy column names with much more sophisticated ones

Conflicts:
	q
All command line arguments are now decoded from preferred encoding (unfortunately only ascii input delimiters are now supported) and column names are decoded from file encoding.