Flatten the table of contents.

Remove the "Guide" and expose the modeling and solving non-linear
least squares in the left hand side navigation bar.

Change-Id: Ibbb4f0f580a5981165a0945570fc0f4c4ea559e9

docs/source/guide.rst

diff --git a/docs/source/guide.rst b/docs/source/guide.rst
deleted file mode 100644
index bcf6bc8..0000000
--- a/docs/source/guide.rst
+++ /dev/null
@@ -1,12 +0,0 @@
-.. _chapter-users-guide:
-
-============
-User's Guide
-============
-
-.. toctree::
-   :maxdepth: 2
-
-   nnls_modeling
-   nnls_solving
-   gradient_solver

docs/source/index.rst

diff --git a/docs/source/index.rst b/docs/source/index.rst
index 54daed9..ae3be3d 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -21,11 +21,13 @@
    :maxdepth: 1
    :hidden:
 
+   features
    installation
    tutorial
    derivatives
-   guide
-   features
+   nnls_modeling
+   nnls_solving
+   gradient_solver
    faqs
    users
    contributing