Toggle main window hide on tray icon click

- converted openBictoinAction to toggleHideAction
- put GUIUtil functions into a namespace instead of a class
- put window-related functions together in optionsdialog

Reasoning:
- toggle is more typical behaviour
- it's more functional
- better UX

The typical issue with toggling visibility is that when a window
is obscured by other windows but in the 'shown' state, hiding it
isn't what you want. I've added an 'isObscured' function to GUIUtil
that checks several pixels in the window to see if they are visible
on the desktop so that an obscured but shown window can be raised.

Conflicts:

	src/qt/guiutil.cpp
	src/qt/guiutil.h

src/qt/guiutil.cpp

@@ -19,31 +19,33 @@
 #include <QDesktopServices>
 #include <QThread>
 
-QString GUIUtil::dateTimeStr(qint64 nTime)
-{
-    return dateTimeStr(QDateTime::fromTime_t((qint32)nTime));
-}
+namespace GUIUtil {
 
-QString GUIUtil::dateTimeStr(const QDateTime &date)
+QString dateTimeStr(const QDateTime &date)
 {
     return date.date().toString(Qt::SystemLocaleShortDate) + QString(" ") + date.toString("hh:mm");
 }
 
-QFont GUIUtil::bitcoinAddressFont()
+QString dateTimeStr(qint64 nTime)
+{
+    return dateTimeStr(QDateTime::fromTime_t((qint32)nTime));
+}
+
+QFont bitcoinAddressFont()
 {
     QFont font("Monospace");
     font.setStyleHint(QFont::TypeWriter);
     return font;
 }
 
-void GUIUtil::setupAddressWidget(QLineEdit *widget, QWidget *parent)
+void setupAddressWidget(QLineEdit *widget, QWidget *parent)
 {
     widget->setMaxLength(BitcoinAddressValidator::MaxAddressLength);
     widget->setValidator(new BitcoinAddressValidator(parent));
     widget->setFont(bitcoinAddressFont());
 }
 
-void GUIUtil::setupAmountWidget(QLineEdit *widget, QWidget *parent)
+void setupAmountWidget(QLineEdit *widget, QWidget *parent)
 {
     QDoubleValidator *amountValidator = new QDoubleValidator(parent);
     amountValidator->setDecimals(8);
@@ -52,7 +54,7 @@ void GUIUtil::setupAmountWidget(QLineEdit *widget, QWidget *parent)
     widget->setAlignment(Qt::AlignRight|Qt::AlignVCenter);
 }
 
-bool GUIUtil::parseBitcoinURI(const QUrl &uri, SendCoinsRecipient *out)
+bool parseBitcoinURI(const QUrl &uri, SendCoinsRecipient *out)
 {
     if(uri.scheme() != QString("bitcoin"))
         return false;
@@ -97,7 +99,7 @@ bool GUIUtil::parseBitcoinURI(const QUrl &uri, SendCoinsRecipient *out)
     return true;
 }
 
-bool GUIUtil::parseBitcoinURI(QString uri, SendCoinsRecipient *out)
+bool parseBitcoinURI(QString uri, SendCoinsRecipient *out)
 {
     // Convert bitcoin:// to bitcoin:
     //
@@ -111,7 +113,7 @@ bool GUIUtil::parseBitcoinURI(QString uri, SendCoinsRecipient *out)
     return parseBitcoinURI(uriInstance, out);
 }
 
-QString GUIUtil::HtmlEscape(const QString& str, bool fMultiLine)
+QString HtmlEscape(const QString& str, bool fMultiLine)
 {
     QString escaped = Qt::escape(str);
     if(fMultiLine)
@@ -121,12 +123,12 @@ QString GUIUtil::HtmlEscape(const QString& str, bool fMultiLine)
     return escaped;
 }
 
-QString GUIUtil::HtmlEscape(const std::string& str, bool fMultiLine)
+QString HtmlEscape(const std::string& str, bool fMultiLine)
 {
     return HtmlEscape(QString::fromStdString(str), fMultiLine);
 }
 
-void GUIUtil::copyEntryData(QAbstractItemView *view, int column, int role)
+void copyEntryData(QAbstractItemView *view, int column, int role)
 {
     if(!view || !view->selectionModel())
         return;
@@ -139,7 +141,7 @@ void GUIUtil::copyEntryData(QAbstractItemView *view, int column, int role)
     }
 }
 
-QString GUIUtil::getSaveFileName(QWidget *parent, const QString &caption,
+QString getSaveFileName(QWidget *parent, const QString &caption,
                                  const QString &dir,
                                  const QString &filter,
                                  QString *selectedSuffixOut)
@@ -185,7 +187,7 @@ QString GUIUtil::getSaveFileName(QWidget *parent, const QString &caption,
     return result;
 }
 
-Qt::ConnectionType GUIUtil::blockingGUIThreadConnection()
+Qt::ConnectionType blockingGUIThreadConnection()
 {
     if(QThread::currentThread() != QCoreApplication::instance()->thread())
     {
@@ -196,3 +198,23 @@ Qt::ConnectionType GUIUtil::blockingGUIThreadConnection()
         return Qt::DirectConnection;
     }
 }
+
+bool checkPoint(const QPoint &p, const QWidget *w)
+{
+  QWidget *atW = qApp->widgetAt(w->mapToGlobal(p));
+  if(!atW) return false;
+  return atW->topLevelWidget() == w;
+}
+
+bool isObscured(QWidget *w)
+{
+
+  return !(checkPoint(QPoint(0, 0), w)
+           && checkPoint(QPoint(w->width() - 1, 0), w)
+           && checkPoint(QPoint(0, w->height() - 1), w)
+           && checkPoint(QPoint(w->width() - 1, w->height() - 1), w)
+           && checkPoint(QPoint(w->width()/2, w->height()/2), w));
+}
+
+} // namespace GUIUtil
+