tarsnapper: 0.2.1 -> 0.4

- project is not a python library -> move out of pythonPackages.
- also enable tests

pkgs/tools/backup/tarsnapper/remove-argparse.patch

@@ -0,0 +1,10 @@
+--- tarsnapper-0.4-src.org/setup.py	1980-01-02 00:00:00.000000000 +0000
++++ tarsnapper-0.4-src/setup.py	2017-07-16 10:54:36.596499451 +0100
+@@ -45,6 +45,6 @@
+       url='http://github.com/miracle2k/tarsnapper',
+       license='BSD',
+       packages=['tarsnapper'],
+-      install_requires = ['argparse>=1.1', 'pyyaml>=3.09', 'python-dateutil>=2.4.0', 'pexpect>=3.1'],
++      install_requires = ['pyyaml>=3.09', 'python-dateutil>=2.4.0', 'pexpect>=3.1'],
+       **kw
+ )