Log mappings + reorder them to fix issues

[dimateos]

My fix to the issues related to https://github.com/JacquesLucke/blender_vscode/issues/140

• Logs the mapping json to a vscode logging output
• Reorders the mappings to fix breakpoints being triggered in a read-only state instead of the source file

This fix works well for me, but might be worth testing it in other scenarios.