DEBUG ERROR implemented.
DEBUG ERROR implemented.

The new "error" subcommand of the DEBUG command can reply with an user
selected error, specified as its sole argument:

    DEBUG ERROR "LOADING please wait..."

The error is generated just prefixing the command argument with a "-"
character, and replacing newlines with spaces (since error replies can't
include newlines).

The goal of the command is to help in Client libraries unit tests by
making simple to simulate a command call triggering a given error.

spearhead-ea/redis,himoca/redis,himoca/redis,HunanTV/redis,ksarch-saas/redis,HunanTV/redis,louisliangjun/redis,louisliangjun/redis,Hailei/redis,ramonsnir/redis,slfs007/mk-redis,slfs007/mk-redis,ttuna/msot-redis,himoca/redis,splitice/redis,MSOpenTech/redis,ttuna/msot-redis,xuzhezhaozhao/redis_reading,Hailei/redis,ksarch-saas/redis,MSOpenTech/redis,MSOpenTech/redis,jxwr/redis,splitice/redis,MSOpenTech/redis,splitice/redis,ttuna/msot-redis,xuzhezhaozhao/redis_reading,splitice/redis,HunanTV/redis,ttuna/msot-redis,ttuna/msot-redis,louisliangjun/redis,ksarch-saas/redis,spearhead-ea/redis,maodeyi/redis_lua,darksideofthemoo/redis-histogram,ramonsnir/redis,xuzhezhaozhao/redis_reading,jxwr/redis,xuzhezhaozhao/redis_reading,darksideofthemoo/redis-histogram,HunanTV/redis,slfs007/mk-redis,maodeyi/redis_lua,darksideofthemoo/redis-histogram,spearhead-ea/redis,Hailei/redis,ksarch-saas/redis,darksideofthemoo/redis-histogram,maodeyi/redis_lua,jxwr/redis,MSOpenTech/redis,ramonsnir/redis,Hailei/redis,louisliangjun/redis