issue: disallow conflicting parameters.

[robbat2]

Do not allow issue to be called with both a CSR & domain; the domain is
silently ignored, and can be very confusing when you are debugging
issues.

Closes: #32
Signed-off-by: Robin H. Johnson robbat2@gentoo.org

[veeti]

The problem with this is that the domain given is used to generate the filename, so it crashes when issuing with a CSR:

Traceback (most recent call last):
  File "/home/veeti/code/manuale/manuale/cli.py", line 283, in main
    args.func(args)
  File "/home/veeti/code/manuale/manuale/cli.py", line 116, in _issue
    output_path=args.output
  File "/home/veeti/code/manuale/manuale/issue.py", line 82, in issue
    cert_path = os.path.join(output_path, domains[0] + '.crt')
IndexError: list index out of range

[robbat2]

Hmm, why didn't my case catch this...