Add output and labels to quickcmd

[pajawojciech]

Changes

• Custom names for commands, editable via Shift+N
• When name is not empty then it shows instead of command
• Checkbox to display command output in a popup window (Shift+O)
• Config data is stored in separate config file because data structure changed from string array to objects array (in quickcmd-v2.json instead of quickcmd.json)
• If there is no data in new config file then auto migrate from old config

quickcmd window:

Output window:

Old and new settings file:

Issues

• Feature Request: Ability to name or label saved commands in quickcmd dfhack#3420
• show output of commands run via gui/quickcmd dfhack#4998

[chdoc]

Overall, I think this is a pretty nice change and the code looks pretty clean. Please update the configuration filed behavior as discussed in my previous comment and use a canonical value for commands that do not have assigned names.