Add support for de-activating a field (removed from stats)

Author: atiro

src/main/java/de/gwdg/metadataqa/api/configuration/schema/Field.java

@@ -7,6 +7,7 @@ public class Field {
   private String path;
   private List<String> categories;
   private boolean extractable;
+  private boolean inactive;
   private List<Rule> rules;
   private String indexField;
 
@@ -42,6 +43,14 @@ public void setExtractable(boolean extractable) {
     this.extractable = extractable;
   }
 
+  public boolean isInactive() {
+    return inactive;
+  }
+
+  public void setInactive(boolean inactive) {
+    this.inactive = inactive;
+  }
+
   public List<Rule> getRules() {
     return rules;
   }

src/main/java/de/gwdg/metadataqa/api/util/SchemaFactory.java

@@ -51,6 +51,9 @@ public static Schema fromConfig(SchemaConfiguration config) {
       if (field.isExtractable())
         branch.setExtractable();
 
+      if (field.isInactive())
+        branch.setActive(false);
+
       if (field.getRules() != null)
         branch.setRule(field.getRules());