Remove unnecessary packages to speed up build

Dockerfile

@@ -26,7 +26,7 @@ RUN useradd eos-user
 RUN yum -y --nogpg install \
     heimdal-server heimdal-workstation \
     krb5-workstation yum-plugin-priorities \
-    createrepo initscripts less emacs vim nano \
+    createrepo initscripts less nano \
     git parallel compat-libf2c-34 libgfortran \
     gdb gcc-c++ cmake3 libacl-devel perl-Test-Harness \
     rpm-build bzip2 automake autoconf libtool