Rebrand to Bitcoin Core

Only messages for now, executable names and other file names
can be changed later if necessary and safe.

Do not do an all-sweeping change. Some occurences of Bitcoin-Qt need to
be kept:

- Applicationname: this is used to determine the registry entry names,
  we don't want to lose settings over a silly name change.
- Where it refers to the executable name instead of the product name.

src/qt/forms/aboutdialog.ui

@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string>About Bitcoin</string>
+   <string>About Bitcoin Core</string>
   </property>
   <layout class="QHBoxLayout" name="horizontalLayout_2">
    <item>
@@ -50,7 +50,7 @@
           <cursorShape>IBeamCursor</cursorShape>
          </property>
          <property name="text">
-          <string>&lt;b&gt;Bitcoin&lt;/b&gt; version</string>
+          <string>&lt;b&gt;Bitcoin Core&lt;/b&gt; version</string>
          </property>
          <property name="textInteractionFlags">
           <set>Qt::LinksAccessibleByMouse|Qt::TextSelectableByKeyboard|Qt::TextSelectableByMouse</set>
@@ -91,7 +91,7 @@
         <cursorShape>IBeamCursor</cursorShape>
        </property>
        <property name="text">
-        <string notr="true">Copyright &amp;copy; 2009-YYYY The Bitcoin developers</string>
+        <string notr="true">Copyright &amp;copy; 2009-YYYY The Bitcoin Core developers</string>
        </property>
        <property name="textFormat">
         <enum>Qt::RichText</enum>

src/qt/forms/intro.ui

@@ -20,7 +20,7 @@
       <string notr="true">QLabel { font-style:italic; }</string>
      </property>
      <property name="text">
-      <string>Welcome to Bitcoin-Qt.</string>
+      <string>Welcome to Bitcoin Core.</string>
      </property>
      <property name="wordWrap">
       <bool>true</bool>
@@ -46,7 +46,7 @@
    <item>
     <widget class="QLabel" name="label_4">
      <property name="text">
-      <string>As this is the first time the program is launched, you can choose where Bitcoin-Qt will store its data.</string>
+      <string>As this is the first time the program is launched, you can choose where Bitcoin Core will store its data.</string>
      </property>
      <property name="wordWrap">
       <bool>true</bool>
@@ -56,7 +56,7 @@
    <item>
     <widget class="QLabel" name="sizeWarningLabel">
      <property name="text">
-      <string>Bitcoin-Qt will download and store a copy of the Bitcoin block chain. At least %1GB of data will be stored in this directory, and it will grow over time. The wallet will also be stored in this directory.</string>
+      <string>Bitcoin Core will download and store a copy of the Bitcoin block chain. At least %1GB of data will be stored in this directory, and it will grow over time. The wallet will also be stored in this directory.</string>
      </property>
      <property name="wordWrap">
       <bool>true</bool>

src/qt/forms/rpcconsole.ui

@@ -348,7 +348,7 @@
        <item row="17" column="0">
         <widget class="QPushButton" name="showCLOptionsButton">
          <property name="toolTip">
-          <string>Show the Bitcoin-Qt help message to get a list with possible Bitcoin command-line options.</string>
+          <string>Show the Bitcoin-Core help message to get a list with possible Bitcoin command-line options.</string>
          </property>
          <property name="text">
           <string>&amp;Show</string>