Add Quickstart for Library Manager

docs/userguide/lib/index.rst

@@ -9,20 +9,11 @@
     See the License for the specific language governing permissions and
     limitations under the License.
 
-.. _librarymanager:
+.. _userguide_lib:
 
 Library Manager
 ===============
 
-*PlatformIO Library Manager* allows you to organize external embedded libraries.
-You can search for new libraries via
-
-* :ref:`Command Line interface <cmd_lib_search>`
-* `Web 2.0 Library Search <http://platformio.org/#!/lib>`_
-
-You don't need to bother for finding the latest version of library. Due to
-:ref:`cmd_lib_update` command you will have up-to-date external libraries.
-
 To print all available commands and options use:
 
 .. code-block:: bash