implements different disk sizes for different networks on intro

- Creates m_assumed_blockchain_size and m_assumed_chain_state_size on CChainParams.
- Implements access to CChainParams' m_assumed_blockchain_size and m_assumed_chain_state_size on node interface.
- Implements m_assumed_blockchain_size and m_assumed_chain_state_size on qt/intro via node interface.
- Updates release process document with the new CChainParam's values.

src/qt/intro.h

@@ -30,7 +30,8 @@ class Intro : public QDialog
     Q_OBJECT
 
 public:
-    explicit Intro(QWidget *parent = 0);
+    explicit Intro(QWidget *parent = 0,
+                   uint64_t blockchain_size = 0, uint64_t chain_state_size = 0);
     ~Intro();
 
     QString getDataDirectory();
@@ -71,6 +72,8 @@ private:
     QMutex mutex;
     bool signalled;
     QString pathToCheck;
+    uint64_t m_blockchain_size;
+    uint64_t m_chain_state_size;
 
     void startThread();
     void checkPath(const QString &dataDir);