message: Qt: BIP38 dialog string updates
  These strings had been copied from the sign/verify message dialog, and
  seemed out of place. Updated with new strings that (to me) make more
  sense.
diff: <item>
  <widget class="QValidatedLineEdit" name="addressIn_ENC">
  <property name="toolTip">
  - <string>The PIVX address to sign the message with</string>
  + <string>The PIVX address to encrypt</string>
  </property>
  </widget>
  </item>
  <item>
  - <widget class="QPushButton" name="addressBookButton_ENC">
  + <widget class="QToolButton" name="addressBookButton_ENC">
  <property name="toolTip">
  <string>Choose previously used address</string>
  </property>
  <item>
  <widget class="QPushButton" name="encryptKeyButton_ENC">
  <property name="toolTip">
  - <string>Sign the message to prove you own this PIVX address</string>
  + <string>Encrypt the private key for this PIVX address</string>
  </property>
  <property name="text">
  <string>Encrypt &amp;Key</string>
  <item>
  <widget class="QPushButton" name="clearButton_ENC">
  <property name="toolTip">
  - <string>Reset all sign message fields</string>
  + <string>Reset all fields</string>
  </property>
  <property name="text">
  <string>Clear &amp;All</string>
  <item>
  <widget class="QValidatedLineEdit" name="encryptedKeyIn_DEC">
  <property name="toolTip">
  - <string>The PIVX address the message was signed with</string>
  + <string>The encrypted private key</string>
  </property>
  </widget>
  </item>
  <item>
  <widget class="QPushButton" name="decryptKeyButton_DEC">
  <property name="toolTip">
  - <string>Verify the message to ensure it was signed with the specified PIVX address</string>
  + <string>Decrypt the entered key using the passphrase</string>
  </property>
  <property name="text">
  <string>Decrypt &amp;Key</string>
  <item>
  <widget class="QPushButton" name="clearButton_DEC">
  <property name="toolTip">
  - <string>Reset all verify message fields</string>
  + <string>Reset all fields</string>
  </property>
  <property name="text">
  <string>Clear &amp;All</string>
  