feat(@angular/cli): allow overrides on multi-target if builder is same
feat(@angular/cli): allow overrides on multi-target if builder is same

It makes sense and is the only way to allow "ng lint --fix". If the builder is the
same for all targets, overrides are allowed.

Brocco/angular-cli,beeman/angular-cli,geofffilippi/angular-cli,geofffilippi/angular-cli,clydin/angular-cli,clydin/angular-cli,catull/angular-cli,Brocco/angular-cli,angular/angular-cli,clydin/angular-cli,manekinekko/angular-cli,Brocco/angular-cli,angular/angular-cli,hansl/angular-cli,Brocco/angular-cli,DevIntent/angular-cli,filipesilva/angular-cli,DevIntent/angular-cli,ocombe/angular-cli,manekinekko/angular-cli,beeman/angular-cli,catull/angular-cli,filipesilva/angular-cli,filipesilva/angular-cli,DevIntent/angular-cli,angular/angular-cli,hansl/angular-cli,manekinekko/angular-cli,ocombe/angular-cli,ocombe/angular-cli,angular/angular-cli,geofffilippi/angular-cli,hansl/angular-cli,catull/angular-cli,ocombe/angular-cli,beeman/angular-cli,Brocco/angular-cli,DevIntent/angular-cli,catull/angular-cli,DevIntent/angular-cli,filipesilva/angular-cli,ocombe/angular-cli,beeman/angular-cli,hansl/angular-cli,geofffilippi/angular-cli,clydin/angular-cli