test: each app keeps its tests in a tests package

131 test modules sat next to the code they test; instances alone had
51 of them beside views.py and utils.py. They move into a
tests/ package per app, and the JavaScript checks into
webvirtcloud/tests/js. Each non-empty tests.py becomes tests/test_views.py;
the empty generated stubs are removed.

Imports of the app's own modules become absolute, paths built from
__file__ go one level up, the live helper is instances.tests.livetest,
and coverage omits */tests/*. The suite discovers the same 960 tests as
before.

vrtManager/tests/test_live_connection.py

@@ -1,6 +1,6 @@
 """Live checks of bounded connection opens against real libvirt.
 
-Runs only with TEST_LIBVIRT_HOST set (a TCP compute, see instances/livetest.py);
+Runs only with TEST_LIBVIRT_HOST set (a TCP compute, see instances/tests/livetest.py);
 TEST_LIBVIRT_SSH_HOST/_LOGIN add a reachable ssh compute. 192.0.2.1 is
 TEST-NET-1: SYN packets to it are dropped, as for a host that went away
 without a trace.

vrtManager/tests/test_live_nvram.py

@@ -1,7 +1,7 @@
 """Live check that the NVRAM file a migrated VM leaves behind is removed,
 and kept when the destination sees the same directory.
 
-Runs only with TEST_LIBVIRT_HOST set (see instances/livetest.py). The
+Runs only with TEST_LIBVIRT_HOST set (see instances/tests/livetest.py). The
 deletion needs a second host: TEST_LIBVIRT_SSH_HOST (and _LOGIN).
 """
 
@@ -12,7 +12,7 @@ import libvirt
 from django.test import SimpleTestCase
 from lxml import etree
 
-from instances import livetest
+from instances.tests import livetest
 from vrtManager.connection import CONN_SSH, NVRAM_DIR, connection_manager, wvmConnect
 
 NAME = livetest.PREFIX + "nvram"