Huge improvements for docs (#58)

docs/content/doc/development/test.md

@@ -0,0 +1,27 @@
+---
+date: "2019-02-12:00:00+02:00"
+title: "Testing"
+draft: false
+type: "doc"
+menu:
+  sidebar:
+    parent: "development"
+---
+
+# Testing
+
+You can run unit tests with [our `Makefile`]({{< ref "make.md">}}) with
+
+{{< highlight bash >}}
+make test
+{{< /highlight >}}
+
+### Running tests with config
+
+You can run tests with all available config variables if you want, enabeling you to run tests for a lot of scenarios.
+
+To use the normal config set the enviroment variable `VIKUNJA_TESTS_USE_CONFIG=1`.
+
+### Show sql queries
+
+When `UNIT_TESTS_VERBOSE=1` is set, all sql queries will be shown when tests are run.