Merge pull request #739 from control-toolbox/documentation

Review of the documentation

Author: ocots

docs/make.jl

@@ -207,6 +207,8 @@ with_api_reference(src_dir, ext_dir) do api_pages
             "Basic Examples" => [
                 "Energy minimisation" => "example-double-integrator-energy.md",
                 "Time mininimisation" => "example-double-integrator-time.md",
+                "Control-free problems" => "example-control-free.md",
+                "Singular control" => "example-singular-control.md",
             ],
             "Manual" => [
                 "Define a problem" => "manual-abstract.md",
@@ -221,6 +223,7 @@ with_api_reference(src_dir, ext_dir) do api_pages
                 ],
                 "Solution characteristics" => "manual-solution.md",
                 "Plot a solution" => "manual-plot.md",
+                "Differential geometry tools" => "manual-differential-geometry.md",
                 "Compute flows" => [
                     "From optimal control problems" => "manual-flow-ocp.md",
                     "From Hamiltonians and others" => "manual-flow-others.md",