bug #27715: mysqld --character-sets-dir buffer overflow
bug ##26851: Mysql Client --pager Buffer Overflow

Using strmov() to copy an argument may cause overflow 
if the argument's length is bigger than the buffer:
use strmake instead.
Also, we have to encrease the error message buffer size to fit 
the longest message.


client/mysql.cc:
  Fix for 
  bug #27715: mysqld --character-sets-dir buffer overflow
  bug ##26851: Mysql Client --pager Buffer Overflow
    - use strmake() instead of strmov() to avoid buffer overflow.
mysql-test/r/mysql.result:
  Fix for 
  bug #27715: mysqld --character-sets-dir buffer overflow
  bug ##26851: Mysql Client --pager Buffer Overflow
  
    - test result.
mysql-test/t/mysql.test:
  Fix for 
  bug #27715: mysqld --character-sets-dir buffer overflow
  bug ##26851: Mysql Client --pager Buffer Overflow
  
    - test case.
mysys/charset.c:
  Fix for 
  bug #27715: mysqld --character-sets-dir buffer overflow
  bug ##26851: Mysql Client --pager Buffer Overflow
  
    - encrease error message buffer size to fit the (possible) longest message.