Improve startup failures user experience

- Be clear about config errors instead of difficult stack traces
- Fix default values which should not cause startup failures

src/main/groovy/io/kamax/mxisd/spring/ConfigurationFailureAnalyzer.java

@@ -0,0 +1,14 @@
+package io.kamax.mxisd.spring;
+
+import io.kamax.mxisd.exception.ConfigurationException;
+import org.springframework.boot.diagnostics.AbstractFailureAnalyzer;
+import org.springframework.boot.diagnostics.FailureAnalysis;
+
+public class ConfigurationFailureAnalyzer extends AbstractFailureAnalyzer<ConfigurationException> {
+
+    @Override
+    protected FailureAnalysis analyze(Throwable rootFailure, ConfigurationException cause) {
+        return new FailureAnalysis(cause.getMessage(), "Double check the key value", cause);
+    }
+
+}