Replace terminal icons with SVGs

This replaces the existing GIF and PNG icons used by the terminal
bundles with SVGs. It covers all icons except for the terminal view icon
and the derived icon for creating a new terminal view.

Author: HeikoKlare

debug/org.eclipse.debug.terminal/icons/console_view.png

@@ -20,7 +20,7 @@
          point="org.eclipse.ui.console.consoleFactories">
       <consoleFactory
             class="org.eclipse.debug.terminal.ui.TerminalConsoleFactory"
-            icon="icons/console_view.png"
+            icon="icons/console_view.svg"
             label="Terminal">
       </consoleFactory>
    </extension>