Merge branch 'ld/discovery-limit-to-fs' (early part)

* 'ld/discovery-limit-to-fs' (early part): Rename ONE_FILESYSTEM to DISCOVERY_ACROSS_FILESYSTEM GIT_ONE_FILESYSTEM: flip the default to stop at filesystem boundaries Add support for GIT_ONE_FILESYSTEM truncate cwd string before printing error message config.c: remove static keyword from git_env_bool()