Simplify tool backend

The scope of this MR is to simplify the tool support by removing some code duplication. In the new code, main.tcl is responsible to install the tool (always in ::fwfwk::tool, regardless of the type). The tool is always installed main.tcl then call the right task in fwfwk.tcl. fwfwk_${ToolType}.tcl files expose only basic instruction (e.g. open/close/create project files, move generate artifacts..) differences from the previous version: when the clean command is issued, all the files in the project and out directories are removed (previous only some where removed).

The code was tested on llrf_mcav_ctrl(vivado) llrf_scav(xise/rust_hdl) and llrf_mcav_vm(planahead)