Add new user variables for tuning memory usage:

query_alloc_block_size, query_prealloc_size, range_alloc_block_size,transaction_alloc_block_size and transaction_prealloc_size
Add more checks for "out of memory" detection in range optimization


configure.in:
  Added detection of mallinfo
mysql-test/r/variables.result:
  Test of new variables
mysql-test/t/variables.test:
  Test of new variables
sql/ha_berkeley.cc:
  Use init_sql_alloc instead of init_alloc_root for better OOM detection
sql/log_event.cc:
  Add new user variables for tuning memory usage
sql/mysql_priv.h:
  Add new user variables for tuning memory usage
sql/mysqld.cc:
  Add new user variables for tuning memory usage
sql/opt_ft.cc:
  Add new user variables for tuning memory usage
sql/opt_ft.h:
  Add new user variables for tuning memory usage
sql/opt_range.cc:
  Add new user variables for tuning memory usage
  Add more checks for out of memory conditions
sql/opt_range.h:
  Add new user variables for tuning memory usage
sql/set_var.cc:
  Add new user variables for tuning memory usage
sql/sql_acl.cc:
  Add new user variables for tuning memory usage
sql/sql_class.h:
  Add new user variables for tuning memory usage
sql/sql_delete.cc:
  Add new user variables for tuning memory usage
sql/sql_parse.cc:
  Add new user variables for tuning memory usage
sql/sql_select.cc:
  Add new user variables for tuning memory usage
sql/sql_test.cc:
  Add information about memory useage if system supports mallinfo()
sql/sql_udf.cc:
  Add new user variables for tuning memory usage
sql/sql_update.cc:
  Add new user variables for tuning memory usage
sql/table.cc:
  Add new user variables for tuning memory usage

sql/sql_class.h

@@ -327,6 +327,11 @@ struct system_variables
   ulong table_type;
   ulong default_week_format;
   ulong max_seeks_for_key;
+  ulong range_alloc_block_size;
+  ulong query_alloc_block_size;
+  ulong query_prealloc_size;
+  ulong trans_alloc_block_size;
+  ulong trans_prealloc_size;
 
   my_bool log_warnings;
   my_bool low_priority_updates;