Added macros which allow for testing locally if log is enabled or not.
server/Makefile
Added directory creation command to Makefile. This fixes problem where errmsg.sys was copied to MaxScale/mysql instead of MaxScale/mysql/errmsg.sys
dcb.b
Added external variable which carries the information of enabled logs from log_manager.cc
gateway.c
Tuned logging.
Replaced fprintf's with log write commands, removed the second argument from call of mysql_reset_thd_for_next_command(thd) according to changes in mariadb/5.5/sql/sql_parse.c #rev 3958.
server/Makefile
Instead of installing MaxScale.cnf (and overwriting previous config file), install MaxScale_template.cnf to DEST directory.
config.c
Replace references to 'Gateway' with 'MaxScale', change configuration parameter 'auth' to 'passwd' as it is named in other instances where referenced to password.
