tests: Windows compatibility fixes
- printenv.py, md5sum.py, simplemerge, test-archive, test-merge1,
test-merge-symlinks: set standard streams to binary mode
- test-encode: replace "gunzip" by "gzip -d"
- test-hup: requires fifo
abort: Failed to parse .../t/.hg/hgrc
File contains no section headers.
file: .../t/.hg/hgrc, line: 1
'invalid\n'
updating working directory
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
[paths]
default = .../foo%%bar
default = .../foo%bar
bundle.mainreporoot=.../foobar
defaults.backout=-d "0 0"
defaults.commit=-d "0 0"
defaults.debugrawcommit=-d "0 0"
defaults.tag=-d "0 0"
paths.default=.../foo%bar
ui.slash=True