mod_mam: Support both spellings of XEP-0334 processing hints until XEP is clarified
mod_mam: Support both spellings of XEP-0334 processing hints until XEP is clarified

LanceJenkinZA/prosody-modules,heysion/prosody-modules,heysion/prosody-modules,Craige/prosody-modules,Craige/prosody-modules,LanceJenkinZA/prosody-modules,LanceJenkinZA/prosody-modules,LanceJenkinZA/prosody-modules,Craige/prosody-modules,heysion/prosody-modules,LanceJenkinZA/prosody-modules,Craige/prosody-modules,Craige/prosody-modules,heysion/prosody-modules,heysion/prosody-modules