archive: use util.opener when archiving files.
This simplifies the code a bit and makes it easier to support symlinks.
adding foo
adding bar
adding baz/bletch
test-archive-TIP/.hg_archival.txt
test-archive-TIP/bar
test-archive-TIP/baz/bletch
test-archive-TIP/foo
test-archive-TIP/.hg_archival.txt
test-archive-TIP/bar
test-archive-TIP/baz/bletch
test-archive-TIP/foo
Archive: archive.zip
testing: test-archive-TIP/.hg_archival.txt OK
testing: test-archive-TIP/bar OK
testing: test-archive-TIP/baz/bletch OK
testing: test-archive-TIP/foo OK
No errors detected in compressed data of archive.zip.
test/.hg_archival.txt
test/bar
test/baz/bletch
test/foo
test/.hg_archival.txt
test/bar
test/foo
test-TIP/.hg_archival.txt
test-TIP/bar
test-TIP/baz/bletch
test-TIP/foo
True
abort: archive prefix contains illegal components
Archive: test.zip
testing: test/.hg_archival.txt OK
testing: test/bar OK
testing: test/baz/bletch OK
testing: test/foo OK
No errors detected in compressed data of test.zip.
test-TIP/.hg_archival.txt
test-TIP/bar
test-TIP/baz/bletch
test-TIP/foo