file: updates for Windows

Mainly, [file join] should leave the trailing slash
on c:/

Signed-off-by: Steve Bennett <steveb@workware.net.au>
glob: fix some glob2.test tests on windows

Signed-off-by: Steve Bennett <steveb@workware.net.au>
file copy: Use binary mode when reading and writing files

Matters on Windows

Signed-off-by: Steve Bennett <steveb@workware.net.au>
bootstrap: Unix platforms have link()

Signed-off-by: Steve Bennett <steveb@workware.net.au>
try: fix use of catch/uplevel

Use catch {uplevel 1 $script} instead of catch [list uplevel 1 $script]
to ensure that source info is not lost.

Signed-off-by: Steve Bennett <steveb@workware.net.au>