FIX: missing_value is unknown configuration option
"name": "session",
"pattern": "[_/\\\\]ses-([a-zA-Z0-9]+)",
"mandatory": false,
- "directory": "{{root}}{subject}{session}",
- "missing_value": "ses-1"
+ "directory": "{{root}}{subject}{session}"
},
{
"name": "task",
