Add proof-of-concept unittest

Doesn't do anything useful yet.

.gitignore

@@ -5,6 +5,10 @@
 *.o
 .deps
 .dirstamp
+.eggs
+__pycache__
+.pytest_cache
+*.egg-info
 
 # ignore Codeblocks temporary files and build directories.
 # Codeblocks project file (*.cbp) is added although it may contain some user preferences (eg. program's arguments), it may be useful for some people

python/tests/test_mrmailbox.py

@@ -0,0 +1,16 @@
+import pathlib
+
+import pytest
+
+from deltachat import capi
+
+
+@pytest.fixture
+def tmppath(tmpdir):
+    return pathlib.Path(tmpdir.strpath)
+
+
+def test_new():
+    mbox = capi.lib.mrmailbox_new(capi.ffi.NULL, capi.ffi.NULL, capi.ffi.NULL)
+    capi.lib.mrmailbox_close(mbox)
+    assert 0