Links to external resources are missing on new website

[TorstenBlochwitz]

In the old web-site we had some links to (as far as I remember):

• the FMU Checker from Modelon (we should keep it, even it supports FMI 2.0 only and check less features compared to FMPy)
• QTronics (now Synopsys) FMU Toolbox (was this the correct name?) if Andreas agrees
• FMPy repo
• some other stuff

[andreas-junghanns]

The QTronic FMUSDK is discontinued - the code was moved the Reference FMUs github repository.
We should keep the FMUSDK off the current web pages to reduce confusion.

[chrbertsch]

Mentioning the checkers fmpy validation, FMU Compliance Checker (for FMI 2.0), VDM checker is very important.

@t-sommer : shall we create a new page for them, or include them in the FAQ page ?