[Qt] extend validate line edit and btc address validator

- remove btc address length from address validator
- add an optional btc address check in validated line edit that defaults
  to off and is used in GUIUtil::setupAddressWidget()
- an isAcceptable() check is added to validated line edit on focus out
  which only kicks in, when a validator is used with that widget
- remove an isAcceptable() check from sendcoinsentry.cpp
- remove obsolete attributes from ui files, which are set by calling
  GUIUtil::setupAddressWidget()
- move some more things to GUIUtil::setupAddressWidget() and remove them
  from normal code e.g. placeholder text

src/qt/bitcoinaddressvalidator.h

@@ -1,4 +1,4 @@
-// Copyright (c) 2011-2013 The Bitcoin developers
+// Copyright (c) 2011-2014 The Bitcoin developers
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -7,19 +7,29 @@
 
 #include <QValidator>
 
-/** Base58 entry widget validator.
-   Corrects near-miss characters and refuses characters that are not part of base58.
+/** Base58 entry widget validator, checks for valid characters and
+ * removes some whitespace.
  */
-class BitcoinAddressValidator : public QValidator
+class BitcoinAddressEntryValidator : public QValidator
 {
     Q_OBJECT
 
 public:
-    explicit BitcoinAddressValidator(QObject *parent = 0);
+    explicit BitcoinAddressEntryValidator(QObject *parent);
 
     State validate(QString &input, int &pos) const;
+};
 
-    static const int MaxAddressLength = 35;
+/** Bitcoin address widget validator, checks for a valid bitcoin address.
+ */
+class BitcoinAddressCheckValidator : public QValidator
+{
+    Q_OBJECT
+
+public:
+    explicit BitcoinAddressCheckValidator(QObject *parent);
+
+    State validate(QString &input, int &pos) const;
 };
 
 #endif // BITCOINADDRESSVALIDATOR_H