Remove warning when there is no checker available
Remove warning when there is no checker available

Fixes #53

nerdrew/neomake,neomake/neomake,bonds/neomake,codeinabox/neomake,datanoise/neomake,euclio/neomake,KariusDx/neomake,neomake/neomake,nerdrew/neomake,euclio/neomake,bonds/neomake