Added support for text search and text_score.

docs/guide/text-indexes.rst

@@ -0,0 +1,47 @@
+===========
+Text Search
+===========
+
+After MongoDB 2.4 version, supports search documents by text indexes.
+
+
+Defining a Document with text index
+===================================
+Use the *$* prefix to set a text index, Look the declaration::
+  
+  class News(Document):
+      title = StringField()
+      content = StringField()
+      is_active = BooleanField()
+
+      meta = {'indexes': [
+          {'fields': ['$title', "$content"],
+           'default_language': 'english',
+           'weight': {'title': 10, 'content': 2}
+          }
+      ]}
+
+
+
+Querying
+========
+
+Saving a document::
+
+  News(title="Using mongodb text search",
+       content="Testing text search").save()
+
+  News(title="MongoEngine 0.9 released",
+       content="Various improvements").save()
+
+Next, start a text search using :attr:`QuerySet.search_text` method::
+  
+  document = News.objects.search_text('testing').first()
+  document.title # may be: "Using mongodb text search"
+  
+  document = News.objects.search_text('released').first()
+  document.title # may be: "MongoEngine 0.9 released"
+
+
+
+