CodeLingo setup (#224)

.github/CONTRIBUTING_TEMPLATE.md

@@ -0,0 +1,46 @@
+<!-- use this template to generate the contributor docs with the following command: `$ lingo run docs --template CONTRIBUTING_TEMPLATE.md  --output CONTRIBUTING.md` -->
+# Contributing
+
+## Please contribute
+
+All PR's are welcome
+
+## Coding Style
+
+In order to maintain a consistent style across the codebase, the following coding style has been adopted:
+
+- Function names use PascalCase (func SomeFunc()).
+- Function names using acronyms are capitilised (func SendHTTPRequest()).
+- Variable names use CamelCase (var someVar()).
+- Coding style uses gofmt.
+- Const variables are CamelCase depending on exported items.
+- In line with gofmt, for loops and if statements don't require parenthesis.
+
+Block style example:
+```go
+func SendHTTPRequest(method, path string, headers map[string]string, body io.Reader) (string, error) {
+    result := strings.ToUpper(method)
+
+    if result != "POST" && result != "GET" && result != "DELETE" {
+        return "", errors.New("Invalid HTTP method specified.")
+    }
+
+    req, err := http.NewRequest(method, path, body)
+    if err != nil {
+        return "", err
+    }
+
+    for k, v := range headers {
+        req.Header.Add(k, v)
+    }
+    ...
+}
+```
+
+## Effective Go Guidelines
+[CodeLingo](https://codelingo.io) automatically checks every pull request against the following guidelines from [Effective Go](https://golang.org/doc/effective_go.html).
+
+{{range .}}
+### {{.title}}
+{{.body}}
+{{end}}