datanucleus.autoStartMechanismMode should be marked as 'Removed'

[wusiqi...@lightinthebox.com.INVALID]

hello, everyone:
    I checked datanucleus.autoStartMechanismMode has always set to 'ignored', 
which means this property is not working and should be marked as 'Removed', but 
it is not

references: 
[HIVE-14152] 
https://github.com/apache/hive/blob/169cb8d597d2bc449466329dfa7804b7e73d286d/standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/PersistenceManagerProvider.java#L598
https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=27842758#ConfigurationProperties-datanucleus.autoStartMechanismMode