Each core should use its tools at the specified version

[ffissore]

When multiple versions of the same tool are installed (say avrdude, version 5 and 6), and two cores specify them as dependencies, if core using avrdude 6 uses generic runtime.tools.avrdude.path variable, it may end up using avrdude 5

This happens because runtime.tools* variables are generated once every time packages are initialized, the order is not known in advance, so that the generic variable gets overwritten.

Workaround is to use variables containing versions, like runtime.tools.avrdude-6.0.1-arduino5.path

Fix the IDE so that it sets the generic runtime.tools.avrdude.path variable to the one matching the version specified in related package_*_index.json, whenever a board (core) is selected