Wrong case in 'img' tag 'src' attributes

[henrikt-ma]

In a small number of cases, image files are referred to using an upper case PNG filename extension:

➜  ThermofluidStream-main git:(main) ✗ git grep '.PNG' -- '*.mo' | cat
ThermofluidStream/FlowControl/MCV.mo:<p><img src=\"modelica://ThermoFluidStream/Resources/Doku/ThermofluidStream.FlowControl.MCV.PNG\"/></p>
ThermofluidStream/Processes/Internal/FlowResistance/laminarTurbulentPressureLoss.mo:<p><img src=\"modelica://Thermofluidstream/Resources/Doku/ThermofluidStream.Processes.Internal.FlowResistance.laminarTurbulentPressureLoss.PNG\"/></p>
ThermofluidStream/Processes/Internal/TurboComponent/dp_tau_const_isentrop.mo:<img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Processes.Internal.dp_tau_const_polytrop_skewness.PNG\"/>
ThermofluidStream/Processes/Internal/TurboComponent/dp_tau_const_isentrop.mo:<img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Processes.Internal.dp_tau_const_polytrop_skewness2.PNG\"/>
ThermofluidStream/Topology/Internal.mo:<p><img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Topology.Internal.SplitterRatio.PNG\"/><img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Topology.Internal.SplitterRatio2.PNG\"/></p>
ThermofluidStream/Undirected/Processes/TransportDelay.mo:<p><img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Processes.Tests.TransportDelay_artefacts2.PNG\"/> <img src=\"modelica://ThermofluidStream/Resources/Doku/ThermofluidStream.Processes.Tests.TransportDelay_artefacts.PNG\"/> </p>

This does not match the few cases of files actually having upper case in the filename extension:

➜  ThermofluidStream-main git:(main) ✗ find . -name '*.PNG'           
./ThermofluidStream/Resources/Doku/ThermofluidStream.Topology.Internal.SplitterRatio.PNG
./ThermofluidStream/Resources/Doku/ThermofluidStream.FlowControl.MCV.PNG
./ThermofluidStream/Resources/Doku/ThermofluidStream.Processes.Internal.FlowResistance.laminarTurbulentPressureLoss.PNG
./ThermofluidStream/Resources/Doku/ThermofluidStream.Topology.Internal.SplitterRatio2.PNG
./doc/VideoThermoFluidCover.PNG

On case sensitive file systems, this will result in missing images in the documentation.

I would recommend fixing this by consistently using the more common variant with png in lower case.