bookmarks and links to bookmarks.

This patch adds the following features :

1. Inserting hyperlinks

   -- User has a choice of inserting a link by specifying the target and the
link text.
   -- The user may fetch the title from the web page itself (contents of the
"title" tag ). This feature also handles URL redirects.This feature will especially
help in cases when a user has a list of links referred to and a list of references
has to be created. Just copy/pasting the URL, clicking fetch and then insert will do the job.

2. Linking to bookmarks

   -- A user can specify a bookmark name and the link text. To help the user
with inserting a bookmark, an auto completer is used.

3. Adding Bookmark using a labeled widget ( similar to the way footnote and
endnote labels are entered)

4. Improvement to the Manage Bookmarks ui by adding feature to insert a bookmark
and fixing bugs.

A list of commit headlines follow :

    Added licenses
    Fixed Insert and Rename feature in ManageBookmarks.
    Deleted Advanced options.
    Combined bookmark name line edit and the list widget into an editable combobox.
    Finised Internationalization
    Modify insertText() to accomodate links
    Merged LinkedInsertionDialog, WeblinkInsertionWidget and
    Add a new bookmark to the list as it is added
    Simple Link insertion finished.
    Added the SimpleLinkWidget to the references dock
    sg