Change project layout and use go.mod

pkg/highlight/ftdetect.go

@@ -0,0 +1,18 @@
+package highlight
+
+import "regexp"
+
+// MatchFiletype will use the list of syntax definitions provided and the filename and first line of the file
+// to determine the filetype of the file
+// It will return the corresponding syntax definition for the filetype
+func MatchFiletype(ftdetect [2]*regexp.Regexp, filename string, firstLine []byte) bool {
+	if ftdetect[0].MatchString(filename) {
+		return true
+	}
+
+	if ftdetect[1] != nil {
+		return ftdetect[1].Match(firstLine)
+	}
+
+	return false
+}