added css line numbering for documantation

plugins/org.yakindu.sct.doc.user/css/custom.css

@@ -265,3 +265,22 @@ div.example {
 .to-be-written {
 	background-color: yellow;
 }
+
+
+body {counter-reset: h1}
+h1 {counter-reset: h2}
+h2 {counter-reset: h3}
+h3 {counter-reset: h4}
+h4 {counter-reset: h5}
+h5 {counter-reset: h6}
+
+h1:before {counter-increment: h1; content: counter(h1) ". "}
+h2:before {counter-increment: h2; content: counter(h1) "." counter(h2) ". "}
+h3:before {counter-increment: h3; content: counter(h1) "." counter(h2) "." counter(h3) ". "}
+h4:before {counter-increment: h4; content: counter(h1) "." counter(h2) "." counter(h3) "." counter(h4) ". "}
+h5:before {counter-increment: h5; content: counter(h1) "." counter(h2) "." counter(h3) "." counter(h4) "." counter(h5) ". "}
+h6:before {counter-increment: h6; content: counter(h1) "." counter(h2) "." counter(h3) "." counter(h4) "." counter(h5) "." counter(h6) ". "}
+
+h1.nocount:before h2.nocount:before, h3.nocount:before, h4.nocount:before, h5.nocount:before, h6.nocount:before { content: ""; counter-increment: none } 
+
+