Fixed minor typo mistakes.

base/src/org/compiere/model/PO.java

@@ -2687,7 +2687,7 @@ public abstract class PO
 
 	/**
 	 * 	Encrypt data.
-	 * 	Not: LOB, special values/Obkects
+	 * 	Not: LOB, special values/Objects
 	 *	@param index index
 	 *	@param xx data
 	 *	@return xx

base/src/org/compiere/model/POInfo.java

@@ -32,7 +32,7 @@ import org.compiere.util.DisplayType;
 import org.compiere.util.Env;
 
 /**
- *  Persistet Object Info.
+ *  Persistent Object Info.
  *  Provides structural information
  *
  *  @author Jorg Janke
@@ -365,7 +365,7 @@ public class POInfo implements Serializable
 	}   //  getColumnSQL
 
 	/**
-	 *  Is Column Virtal?
+	 *  Is Column Virtual?
 	 *  @param index index
 	 *  @return true if column is virtual
 	 */

base/src/org/compiere/util/DisplayType.java

@@ -196,7 +196,7 @@ public final class DisplayType
 	}	//	isText
 
 	/**
-	 *	Returns truem if DisplayType is a Date.
+	 *	Returns true if DisplayType is a Date.
 	 *  (stored as Timestamp)
 	 *  @param displayType Display Type
 	 *  @return true if date