ok stsp@

This functionality is better suited for gotadmin because it is technically a server-side repository operation when we consider the 'got' tool as the client-side tool. I have plans to move 'got import' into gotadmin as well. ok op@

ok stsp@

Add detection for headers which are included portably, and remove them.

Cast printf argument of type time_t to long long to match the %lld format specifier on platforms where this might not be the case.

This introduces an area for helper scripts when dealing with -portable syncing from upstream, releases, etc. See the README.md file for further information.

This is included portably.