[Serusers] Feature request: Textops function to remove ALL header fields of name x

[Martin Koenig]

Hello,

I think it would make sense to implement a function in textops similar 
to remove_hf(x) but remove_all_hf(x) in order to be sure a certain 
header field is not present any more.

The specific scenario is setting up a RFC3323/3325-compilant platform, 
where it is imperative that untrusted nodes are not able to inject any 
"P-Asserted-Identity" header field into trusted nodes. I'm not sure 
remove_hf() does the job in this case.

With best regards,
Martin