[mqtt-exporter] New chart (#33)

* [mqtt-exporter] New chart

* Don't enable Metrics for testing

* Fix linting issues

charts/mqtt-exporter/.helmignore

@@ -0,0 +1,26 @@
+# Patterns to ignore when building packages.
+# This supports shell glob matching, relative path matching, and
+# negation (prefixed with !). Only one pattern per line.
+.DS_Store
+# Common VCS dirs
+.git/
+.gitignore
+.bzr/
+.bzrignore
+.hg/
+.hgignore
+.svn/
+# Common backup files
+*.swp
+*.bak
+*.tmp
+*~
+# Various IDEs
+.project
+.idea/
+*.tmproj
+.vscode/
+# OWNERS file for Kubernetes
+OWNERS
+# helm-docs templates
+*.gotmpl