Travis build tests fail

[berezovskyi]

Make itself is performed successfully (https://travis-ci.org/berezovskyi/4store/jobs/215606812#L948).

make[1]: Entering directory `/home/travis/build/berezovskyi/4store/tests'
(cd query && pwd && ./setup.sh --autorun)
/home/travis/build/berezovskyi/4store/tests/query
Failed to create store directory '/var/lib/4store/query_test_travis': No such file or directory
4store[15797]: lock.c:39 failed to open metadata file /var/lib/4store/query_test_travis/metadata.nt for locking: No such file or directory
4store[15797]:  1: ../../src/backend/4s-backend() [0x411b81]
4store[15797]:  2: ../../src/backend/4s-backend() [0x40393b]
4store[15797]:  3: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x2b4ffc0447ed]
4store[15797]:  4: ../../src/backend/4s-backend() [0x403989]
make[1]: *** [test-query] Error 1

Perhaps we should use a directory like /tmp/4store/query_test_travis.

[berezovskyi]

From @swh:

The tests require /var/lib/4store to exist, and be writable by the test user.