mcntp: some manpages

• Mcntp general description
• Manualpage for acl.3
• Manualpage for acltest.1
• Manualpage for groupdump.1
• Manualpage for keygen.8
• Manualpage for mcchat.1
• Manualpage for mcntp.5
• Manualpage for mcntp.conf.5
• Manualpage for mcrcv.8
• Manualpage for mcxmit.8
• Manualpage for mess.1
• Manualpage for rctest.1
• Manualpage for read_conf.3
• Manualpage for rmd.1
• Manualpage for rmd.3
• Manualpage for stricmp.3
• Manualpage for stripcr.3
• Manualpage for stristr.3
• Manualpage for yawgmoth.8