ifpps: add option that omits CSV header

Adds option -o|--omit-header which does not print the CSV header
e.g. when the user does not need it.

Signed-off-by: Jon Schipp <jonschipp@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
ifpps: man: document new option to omit CSV header

Manual page entry for option -c|--omit-header.

Signed-off-by: Jon Schipp <jonschipp@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
ifpps: man: grammar and typo edits

Removed, word "be", which was seen twice and removed unnecessary comma.

Signed-off-by: Jon Schipp <jonschipp@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>