regtools: completely rework qeditor, improve soc desc library and tools

The graphical editor can now display and editor description files.
The library has been improved to provide more useful function.
The XML format has been slightly changed: only one soc is allowed per file
(this is was already de facto the case since <soc> was the root tag).
Also introduce a DTD to validate the files.

Change-Id: If70ba35b6dc0242bdb87411cf4baee9597798aac

utils/regtools/qeditor/std_analysers.h

@@ -21,7 +21,6 @@
 
 class ClockAnalyser : public Analyser
 {
-    Q_OBJECT
 public:
     ClockAnalyser(const SocRef& soc, IoBackend *backend);
     virtual ~ClockAnalyser();
@@ -50,7 +49,7 @@ private:
 /**
  * EMI analyser
  */
-class EmiAnalyser : public Analyser
+class EmiAnalyser : public QObject, public Analyser
 {
     Q_OBJECT
 public:
@@ -96,7 +95,6 @@ private:
  */
 class PinAnalyser : public Analyser
 {
-    Q_OBJECT
 public:
     PinAnalyser(const SocRef& soc, IoBackend *backend);
     virtual ~PinAnalyser();