[Qt] rename rpcconsole window

- rework window title to not include Bitcoin - in front, as no other
  dialog does this
- favor a connect() call over an own function for clearing the traffic
  graph
- write monospace lowercase (seems to be correct after some web search)
  and add a comment that we should avoid / remove fixed font sizes

src/qt/rpcconsole.cpp

@@ -205,6 +205,7 @@ RPCConsole::RPCConsole(QWidget *parent) :
     ui->messagesWidget->installEventFilter(this);
 
     connect(ui->clearButton, SIGNAL(clicked()), this, SLOT(clear()));
+    connect(ui->btnClearTrafficGraph, SIGNAL(clicked()), ui->trafficGraph, SLOT(clear()));
 
     // set OpenSSL version label
     ui->openSSLVersion->setText(SSLeay_version(SSLEAY_VERSION));
@@ -317,7 +318,7 @@ void RPCConsole::clear()
     ui->messagesWidget->document()->setDefaultStyleSheet(
                 "table { }"
                 "td.time { color: #808080; padding-top: 3px; } "
-                "td.message { font-family: Monospace; font-size: 12px; } "
+                "td.message { font-family: monospace; font-size: 12px; } " // Todo: Remove fixed font-size
                 "td.cmd-request { color: #006060; } "
                 "td.cmd-error { color: red; } "
                 "b { color: #006060; } "
@@ -483,8 +484,3 @@ void RPCConsole::updateTrafficStats(quint64 totalBytesIn, quint64 totalBytesOut)
     ui->lblBytesIn->setText(FormatBytes(totalBytesIn));
     ui->lblBytesOut->setText(FormatBytes(totalBytesOut));
 }
-
-void RPCConsole::on_btnClearTrafficGraph_clicked()
-{
-    ui->trafficGraph->clear();
-}