Added XSLTTemplate, functions that add it to transform area and documentation for that function (#144)

Co-authored-by: widlam <mikolaj.widla@gmail.com>
Reviewed-on: #144
Reviewed-by: Adam Bem <bema@noreply.example.com>
Co-authored-by: Mikolaj Widla <widlam@noreply.example.com>
Co-committed-by: Mikolaj Widla <widlam@noreply.example.com>

Frontend/assets/samples/XSLTTemplate.xslt

@@ -0,0 +1,14 @@
+<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+    xmlns:b="http://www.release11.com/book" xmlns:p="http://www.release11.com/person"
+    xmlns:l="http://www.release11.com/library">
+    <xsl:template match="/">
+        <Library>
+            <ReaderCount>
+                <xsl:value-of select="count(//p:person)" />
+            </ReaderCount>
+            <BookCount>
+                <xsl:value-of select="count(/l:library/l:bookList/b:book)" />
+            </BookCount>
+        </Library>
+    </xsl:template>
+</xsl:stylesheet>

Frontend/assets/scripts/tools/scripts.js

@@ -84,6 +84,24 @@ function fillDefaultXML(element) {
     }
 }
 
+
+/**
+ * The `fillDefaultXSLT()` function fetches a default XSLT template from the server and sets the value of the element with id "transformArea" to the fetched template.
+ * 
+ * @function
+ * @name fillDefaultXSLT
+ * @kind function
+ * @returns {void}
+ */
+function fillDefaultXSLT() {
+    const serverAddress = window.location.protocol + "//" + window.location.hostname + ":8086";
+    fetch(serverAddress + "/assets/samples/XSLTTemplate.xslt")
+        .then( response => response.text() )
+        .then( (XSTLTemplate) => {
+            document.getElementById('transformArea').value = XSTLTemplate;
+        } )   
+}
+
 /**
 * It sets default content for the element an changes it's color to grey
 * 

Frontend/tools/xslt.html

@@ -51,7 +51,14 @@
                     onfocus="clearDefaultContent(this, 'Insert XML here');"></textarea>
                 <br><br>
 
+                <div class="display-space-between">
                     <label for="transformArea"><b>Insert your XSLT:</b></label>
+                    <div>
+                        <button class="action-button active" id="defaultXSLTButton" style="padding: 3px 10px;"
+                            onclick="fillDefaultXSLT()">Insert default XSLT
+                        </button>
+                    </div>
+                </div>
                 <textarea id="transformArea" name="transformArea" rows="15"
                     class="textarea-300 bordered-field vertically-resizeable max-width"
                     onblur="setDefaultContent(this, 'Insert XSLT here');"