added Monokai theme color scheme in scintilla editor

src/Preferences.ui

@@ -253,6 +253,11 @@
            <property name="text">
             <string>For Dark Background</string>
            </property>
+          </item>
+	   <item>
+           <property name="text">
+            <string>Monokai</string>
+           </property>
           </item>
           <item>
            <property name="text">

src/scintillaeditor.cpp

@@ -113,6 +113,25 @@ void ScintillaEditor::forDarkBackground()
 	qsci->setMarginsForegroundColor(QColor("#fff"));
 
 }
+
+void ScintillaEditor::Monokai()
+{
+	lexer->setPaper("#272822");
+	lexer->setColor(QColor("#f8f8f2")); // -> Style: Default text
+	lexer->setColor(QColor("#66c3b3"), QsciLexerCPP::Keyword);	    // -> Style: Keyword	
+	lexer->setColor(QColor("#79abff"), QsciLexerCPP::KeywordSet2);	    // -> Style: KeywordSet2
+	lexer->setColor(QColor("#ccdf32"), QsciLexerCPP::CommentDocKeyword);	    // -> used in comments only like /*! \cube */
+	lexer->setColor(QColor("#ffffff"), QsciLexerCPP::GlobalClass);	    // -> Style: GlobalClass
+	lexer->setColor(QColor("#d8d8d8"), QsciLexerCPP::Operator);
+	lexer->setColor(QColor("#e6db74"), QsciLexerCPP::DoubleQuotedString);	
+	lexer->setColor(QColor("#75715e"), QsciLexerCPP::CommentLine);
+	lexer->setColor(QColor("#7fb347"), QsciLexerCPP::Number);
+	qsci->setMarkerBackgroundColor(QColor(255, 0, 0, 100), markerNumber);
+	qsci->setCaretLineBackgroundColor(QColor("#3e3d32"));
+	qsci->setMarginsBackgroundColor(QColor("#757575"));
+	qsci->setMarginsForegroundColor(QColor("#f8f8f2"));
+}
+
 void ScintillaEditor::noColor()
 {
 	lexer->setPaper(Qt::white);
@@ -132,6 +151,10 @@ void ScintillaEditor::setHighlightScheme(const QString &name)
 	{
 		forDarkBackground();
 	}
+	else if(name == "Monokai")
+	{
+		Monokai();
+	}
 	else if(name == "Off")
 	{
 		noColor();

src/scintillaeditor.h

@@ -20,6 +20,7 @@ public:
 	void initLexer();
 	void forLightBackground();
 	void forDarkBackground();
+	void Monokai();
 	void noColor();
 
 public slots: