qt: define QT_NO_KEYWORDS

QT_NO_KEYWORDS prevents Qt from defining the `foreach`, `signals`,
`slots` and `emit` macros.

Avoid overlap between Qt macros and boost - for example #undef hackiness
in #6421.

Conflicts:
	src/qt/addressbookpage.cpp
	src/qt/peertablemodel.cpp
	src/qt/receivecoinsdialog.cpp
	src/qt/rpcconsole.cpp

Rebased-From: d29ec6c2301e593d577126d1ca85b93307b32bf1
Github-Pull: #6433

src/qt/bitcoin.cpp

@@ -168,11 +168,11 @@ class BitcoinCore: public QObject
 public:
     explicit BitcoinCore();
 
-public slots:
+public Q_SLOTS:
     void initialize();
     void shutdown();
 
-signals:
+Q_SIGNALS:
     void initializeResult(int retval);
     void shutdownResult(int retval);
     void runawayException(const QString &message);
@@ -215,13 +215,13 @@ public:
     /// Get window identifier of QMainWindow (BitcoinGUI)
     WId getMainWinId() const;
 
-public slots:
+public Q_SLOTS:
     void initializeResult(int retval);
     void shutdownResult(int retval);
     /// Handle runaway exceptions. Shows a message box with the problem and quits the program.
     void handleRunawayException(const QString &message);
 
-signals:
+Q_SIGNALS:
     void requestedInitialize();
     void requestedShutdown();
     void stopThread();
@@ -252,7 +252,7 @@ BitcoinCore::BitcoinCore():
 void BitcoinCore::handleRunawayException(const std::exception *e)
 {
     PrintExceptionContinue(e, "Runaway exception");
-    emit runawayException(QString::fromStdString(strMiscWarning));
+    Q_EMIT runawayException(QString::fromStdString(strMiscWarning));
 }
 
 void BitcoinCore::initialize()
@@ -268,7 +268,7 @@ void BitcoinCore::initialize()
              */
             StartDummyRPCThread();
         }
-        emit initializeResult(rv);
+        Q_EMIT initializeResult(rv);
     } catch (const std::exception& e) {
         handleRunawayException(&e);
     } catch (...) {
@@ -285,7 +285,7 @@ void BitcoinCore::shutdown()
         threadGroup.join_all();
         Shutdown();
         qDebug() << __func__ << ": Shutdown finished";
-        emit shutdownResult(1);
+        Q_EMIT shutdownResult(1);
     } catch (const std::exception& e) {
         handleRunawayException(&e);
     } catch (...) {
@@ -314,7 +314,7 @@ BitcoinApplication::~BitcoinApplication()
     if(coreThread)
     {
         qDebug() << __func__ << ": Stopping thread";
-        emit stopThread();
+        Q_EMIT stopThread();
         coreThread->wait();
         qDebug() << __func__ << ": Stopped thread";
     }
@@ -385,7 +385,7 @@ void BitcoinApplication::requestInitialize()
 {
     qDebug() << __func__ << ": Requesting initialize";
     startThread();
-    emit requestedInitialize();
+    Q_EMIT requestedInitialize();
 }
 
 void BitcoinApplication::requestShutdown()
@@ -408,7 +408,7 @@ void BitcoinApplication::requestShutdown()
     ShutdownWindow::showShutdownWindow(window);
 
     // Request shutdown from core thread
-    emit requestedShutdown();
+    Q_EMIT requestedShutdown();
 }
 
 void BitcoinApplication::initializeResult(int retval)
@@ -448,7 +448,7 @@ void BitcoinApplication::initializeResult(int retval)
         {
             window->show();
         }
-        emit splashFinished(window);
+        Q_EMIT splashFinished(window);
 
 #ifdef ENABLE_WALLET
         // Now that initialization/startup is done, process any command-line