Add %hostid%
Add %hostid%

Summary: now we can use "%hostid%" in configs

Test Plan: build it :-)

Reviewed By: @int

Differential Revision: D1826195
glensc/mcrouter,seem-sky/mcrouter,seem-sky/mcrouter,tempbottle/mcrouter,nvaller/mcrouter,seem-sky/mcrouter,nvaller/mcrouter,tempbottle/mcrouter,facebook/mcrouter,seem-sky/mcrouter,reddit/mcrouter,apinski-cavium/mcrouter,leitao/mcrouter,apinski-cavium/mcrouter,evertrue/mcrouter,yqzhang/mcrouter,leitao/mcrouter,reddit/mcrouter,is00hcw/mcrouter,zhlong73/mcrouter,evertrue/mcrouter,yqzhang/mcrouter,synecdoche/mcrouter,evertrue/mcrouter,zhlong73/mcrouter,reddit/mcrouter,synecdoche/mcrouter,zhlong73/mcrouter,nvaller/mcrouter,glensc/mcrouter,apinski-cavium/mcrouter,tempbottle/mcrouter,leitao/mcrouter,is00hcw/mcrouter,easyfmxu/mcrouter,synecdoche/mcrouter,yqzhang/mcrouter,yqzhang/mcrouter,glensc/mcrouter,easyfmxu/mcrouter,easyfmxu/mcrouter,reddit/mcrouter,facebook/mcrouter,tempbottle/mcrouter,easyfmxu/mcrouter,glensc/mcrouter,is00hcw/mcrouter,nvaller/mcrouter,is00hcw/mcrouter,leitao/mcrouter,synecdoche/mcrouter,zhlong73/mcrouter,facebook/mcrouter,evertrue/mcrouter,facebook/mcrouter,apinski-cavium/mcrouter