Added psi-always-enabled-history-dlg patch for Mac OS X.

On Mac OS X history dialog don't get keyboard events after it was disabled.
The patch just disables setEnabled for history dialog.

patches/mac/3050-psi-always-enabled-history-dlg.diff

@@ -0,0 +1,56 @@
+diff --git a/src/historydlg.cpp b/src/historydlg.cpp
+index a3631ad..0a1145a 100644
+--- a/src/historydlg.cpp
++++ b/src/historydlg.cpp
+@@ -256,7 +256,7 @@ void HistoryDlg::highlightBlocks(const QString text)
+ 	QTextCursor cur = ui_.msgLog->textCursor();
+ 	cur.clearSelection();
+ 	cur.movePosition(QTextCursor::Start);
+-	ui_.msgLog->setTextCursor(cur);	
++	ui_.msgLog->setTextCursor(cur);
+
+ 	if (text.isEmpty()) {
+ 		getLatest();
+@@ -266,7 +266,7 @@ void HistoryDlg::highlightBlocks(const QString text)
+ 	QList<QTextEdit::ExtraSelection> extras;
+ 	QTextEdit::ExtraSelection highlight;
+ 	highlight.format.setBackground(Qt::yellow);
+-	highlight.cursor = ui_.msgLog->textCursor();	
++	highlight.cursor = ui_.msgLog->textCursor();
+
+ 	bool found = ui_.msgLog->find(text);
+ 	while (found)
+@@ -586,7 +586,7 @@ void HistoryDlg::displayResult(const EDBResult r, int direction, int max)
+ 					msg = "<span style='color:"+sent_color+"'>" + me->timeStamp().toString("[dd.MM.yyyy hh:mm:ss]")+" &lt;"+ TextUtil::plain2rich(d->pa->nick()) +"&gt; " + msg + "</span>";
+ 				else
+ 					msg = "<span style='color:"+received_color+"'>" + me->timeStamp().toString("[dd.MM.yyyy hh:mm:ss]") + " &lt;" +  TextUtil::plain2rich(from) + "&gt; " + msg + "</span>";
+-				
++
+ 				ui_.msgLog->appendText(msg);
+
+ 			}
+@@ -615,15 +615,23 @@ void HistoryDlg::startRequest()
+ 	if(!ui_.busy->isActive()) {
+ 		ui_.busy->start();
+ 	}
++
++	// Workaround. On MAC OS X this dialog doesn't get keyboard events
++	// after it was disabled. It's mean you can do only one searching
++	// without reopening this dialog.
++#ifndef Q_OS_MAC
+ 	setEnabled(false);
++#endif
+ }
+
+ void HistoryDlg::stopRequest()
+ {
+ 	if(ui_.busy->isActive()) {
+-		ui_.busy->stop();		
++		ui_.busy->stop();
+ 	}
++#ifndef Q_OS_MAC
+ 	setEnabled(true);
++#endif
+ }
+
+ EDBHandle* HistoryDlg::getEDBHandle()