title: full text indexing of recursive nested jsonb structures
body: <p>Lets say I have a book represented like this:</p>
  
  <pre><code>{ title: "Tis no book"
    chapter: 1,
    text: "Hello world this is a book chapter",
    subchapters: [
       {
       chapter: 1.1
       text: "Nested sub chapter"
       subchapters: [
         chapter: 1.1.1
         text: "Nested nested..."
         subchapters: [ ...etc...]
       },
       {
       chapter: 1.2
       text: "Nested sub chapter 2"
       subchapters: [ ...etc...]
       }
     ]
  }
  </code></pre>
  
  <p>Can I use postgres' 9.4 new jsonb/gin (or anything else) to set up a full text index on the <code>"text"</code> field of this recursively nested data structure such that a library of books stored to the database can be searched by text (using the index)?</p>