* use local-vars-hook coupled to setup function for dap
* define new private layer variable `spacemacs--dap-supported-modes` to
configure key bindings. This allows to move the key bindings definition from
`funcs.el` to `packages.el`
* remove duplication of DAP key bindings in READMEs by pointing to the dap layer
documentation
* alphabetically sort package configuration
Move check into function, and add to local-vars hook instead of the mode hook.
This makes the variable changeable at runtime and also as part of local vars.
