Fixed compiler warnings detected by option -Wshadow and -Wunused:

- Removed not used variables and functions
- Added #ifdef around code that is not used
- Renamed variables and functions to avoid conflicts
- Removed some not used arguments

Fixed some class/struct warnings in ndb
Added define IS_LONGDATA() to simplify code in libmysql.c

I did run gcov on the changes and added 'purecov' comments on almost all lines that was not just variable name changes

mysql-test/t/mysql.test

@@ -44,7 +44,7 @@ unlock tables;
 drop table t1;
 
 #
-# BUG#16217 - MySQL client misinterpretes multi-byte char as escape `\' 
+# BUG#16217 - MySQL client misinterprets multi-byte char as escape `\' 
 #
 
 # new command \C or charset
@@ -241,4 +241,14 @@ drop table t17583;
 --error 1
 --exec $MYSQL test -e "\r  test cyrils_superlonghostnameXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX" 2>&1
 
+#
+# Some coverage of not normally used parts
+#
+
+--disable_query_log
+--exec $MYSQL test -e "show status" 2>&1 > /dev/null
+--exec $MYSQL --help 2>&1 > /dev/null
+--exec $MYSQL --version 2>&1 > /dev/null
+--enable_quary_log
+
 --echo End of 5.0 tests