In order to install shutter you need to install the Nux Dextop Repo. We will start with importing the official GPG key of Nux Dextop repository.

rpm --import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro

Next install the Nux Dextop Repo.

sudo rpm -Uvh http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-5.el7.nux.noarch.rpm

Now verify that Nux Dextop repository is successfully installed.

yum repolist

We can now list all the packages available from the Nux Dextop repo.

yum --disablerepo="*" --enablerepo="nux-dextop" list available | more

So now we can install Shutter like any other package using yum.

sudo yum install shutter