Incompatible with KNIME version 4

[sverhoeven]

A major release of KNIME Analytics Platform, version 4, is about to be released.

The 3D-e-Chem KNIME nodes have their KNIME dependencies pinned to >=3.X.0 and <4.0.0 and the nodes use KNIME v3 p2 update sites.

Also since KNIME 3.7 the KNIME SDK was replaced with Eclipse and a KNIME target platform, see https://github.com/knime/knime-sdk-setup

Without a new release of the 3D-e-Chem KNIME nodes and it's 3D-e-Chem dependencies, they will not be install-able in the new KNIME version.