explicitly disable txt and pdf

Author: andiwand

app/src/main/java/at/tomtasche/reader/background/OdrCoreLoader.java

@@ -81,6 +81,8 @@ private void translate(Options options, Result result) throws Exception {
         coreOptions.password = options.password;
         coreOptions.editable = options.translatable;
         coreOptions.ooxml = doOoxml;
+        coreOptions.txt = false;
+        coreOptions.pdf = false;
 
         Boolean usePaging = configManager.getBooleanConfig("use_paging");
         if (usePaging == null || usePaging) {