HADOOP-13690. Fix typos in core-default.xml. Contributed by Yiqun Lin

hadoop-common-project/hadoop-common/src/main/resources/core-default.xml

@@ -93,7 +93,7 @@
   <description>
     The name of the Network Interface from which the service should determine
     its host name for Kerberos login. e.g. eth2. In a multi-homed environment,
-    the setting can be used to affect the _HOST subsitution in the service
+    the setting can be used to affect the _HOST substitution in the service
     Kerberos principal. If this configuration value is not set, the service
     will use its default hostname as returned by
     InetAddress.getLocalHost().getCanonicalHostName().
@@ -400,7 +400,7 @@
     The number of levels to go up the group hierarchy when determining
     which groups a user is part of. 0 Will represent checking just the
     group that the user belongs to.  Each additional level will raise the
-    time it takes to exectue a query by at most
+    time it takes to execute a query by at most
     hadoop.security.group.mapping.ldap.directory.search.timeout.
     The default will usually be appropriate for all LDAP systems.
   </description>
@@ -1939,7 +1939,7 @@
   <value>dr.who=;</value>
   <description>
     Static mapping of user to groups. This will override the groups if
-    available in the system for the specified user. In otherwords, groups
+    available in the system for the specified user. In other words, groups
     look-up will not happen for these users, instead groups mapped in this
     configuration will be used.
     Mapping should be in this format.