Support stdin via pipe, but not yet python3

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
closes #5 read the file from standard input pipe

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
closes #4 detect "python-magic" debian package in setup.py

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
closes #5; re-opened from stdin pipe

 * refactoring, and add test code

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
increase version and update documents

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Merge branch 'devel'