add uconvert to .gitignore
add uconvert to .gitignore

Signed-off-by: John Shahid <7c84c4d4148af24079897a92115d562877358578@pivotal.io>

cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release