Merge branch 'mc/netrc-service-names'

"netrc" credential helper has been improved to understand textual service names (like smtp) in addition to the numeric port numbers (like 25). * mc/netrc-service-names: contrib: better support symbolic port names in git-credential-netrc contrib: warn for invalid netrc file ports in git-credential-netrc contrib: use a more portable shebang for git-credential-netrc