Don't set group tags

They are unused in Fedora.

libsigc++20.spec

@@ -6,7 +6,6 @@ Version:        2.10.0
 Release:        1%{?dist}
 Summary:        Typesafe signal framework for C++
 
-Group:          System Environment/Libraries
 License:        LGPLv2+
 URL:            http://libsigc.sourceforge.net/
 Source0:        http://download.gnome.org/sources/libsigc++/%{release_version}/libsigc++-%{version}.tar.xz
@@ -30,7 +29,6 @@ starting with version 1.1.2, uses libsigc++20.
 
 %package devel
 Summary:        Development tools for the typesafe signal framework for C++
-Group:          Development/Libraries
 Requires:       %{name}%{?_isa} = %{version}-%{release}
 
 %description devel
@@ -40,7 +38,6 @@ needed for development with %{name}.
 
 %package        doc
 Summary:        Documentation for %{name}, includes full API docs
-Group:          Documentation
 BuildArch:      noarch
 Requires:       %{name} = %{version}-%{release}
 
@@ -89,6 +86,7 @@ find $RPM_BUILD_ROOT -type f -name "*.la" -exec rm -f {} ';'
 %changelog
 * Tue Sep 20 2016 Kalev Lember <klember@redhat.com> - 2.10.0-1
 - Update to 2.10.0
+- Don't set group tags
 
 * Mon Jul 18 2016 Kalev Lember <klember@redhat.com> - 2.9.3-1
 - Update to 2.9.3