env: fix a deploy glitch with the newly introduced `[inherit] htdocs_dir` setting (r10167).
env: fix a deploy glitch with the newly introduced `[inherit] htdocs_dir` setting (r10167).

By default its value is `''`, which translates to `'.'` due to `os.path.normpath`, so this results in `trac-admin ... deploy /target` creating a recursive copy of the current directory below `/target/htdocs/shared`! Avoid this by skipping empty paths.

git-svn-id: f68c6b3b1dcd5d00a2560c384475aaef3bc99487@10406 af82e41b-90c4-0310-8c96-b1721e28e2e2

dafrito/trac-mirror,dafrito/trac-mirror,dafrito/trac-mirror,dafrito/trac-mirror