Merge branch 'jn/gitweb-caching-prep'

* jn/gitweb-caching-prep: gitweb: Move generating page title to separate subroutine gitweb: Add custom error handler using die_error gitweb: Use nonlocal jump instead of 'exit' in die_error gitweb: href(..., -path_info => 0|1) Export more test-related variables when running external tests