Build linux-debian10 (Jan 17, 2021, 3:18:06 PM)

1. added minimal test for IAC escapting (details / githubweb)
2. make buffer const char* since we don't mutate it (details / githubweb)
3. clang tidy fixes (details / githubweb)
4. use fmtlib for status reporting in zmodem (details / githubweb)
5. More zmodem cleanups. (details / githubweb)

Started by upstream project wwiv build number 3397
originally caused by:

• Started by an SCM change

• refs/remotes/origin/main