Update graph

[ocots]

new graph

flowchart TD
O(<a href='https://control-toolbox.org/docs/optimalcontrol/stable/'>OptimalControl</a>) --> B(<a href='https://control-toolbox.org/docs/ctbase/stable/'>CTBase</a>)
O --> D(<a href='https://control-toolbox.org/docs/ctdirect/stable/'>CTDirect</a>)
O --> F(<a href='https://control-toolbox.org/docs/ctflows/stable/'>CTFlows</a>)
P(<a href='https://control-toolbox.org/docs/ctproblems/stable/'>CTProblems</a>) --> F
P --> B
F --> B
D --> B
style O fill:#FFF0F5