stdout output option doesn't output to stdout

[jonblack]

The help documentation states:

-o [ --output ] arg Output file, use 'stdout' to output to screen

Using stdout as the output file results in a file called stdout and not the output being sent to stdout.

Fix this by removing the help text. mkdssp (and probably also mkhssp) should by default output to stdout. Only when -o is specified should it output to a file.

[jonblack]

It turns out this is actually how it's been implemented. 😦 This issue is all about updating the help documentation.