str/cat: Rename from util/string

This still maintains backwards compatability.

Change-Id: Id984a9c2067aaa6986f892c1870834d77b8aec80
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/test/meson.build b/test/meson.build
index 16e1e77..2f1d7f9 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -6,8 +6,8 @@
   'pinned': [stdplus_dep, gtest_main_dep],
   'raw': [stdplus_dep, gmock_dep, gtest_main_dep],
   'signal': [stdplus_dep, gtest_main_dep],
+  'str/cat': [stdplus_dep, gtest_main_dep],
   'util/cexec': [stdplus_dep, gtest_main_dep],
-  'util/string': [stdplus_dep, gtest_main_dep],
   'zstring': [stdplus_dep, gtest_main_dep],
   'zstring_view': [stdplus_dep, gtest_main_dep],
 }
diff --git a/test/util/string.cpp b/test/str/cat.cpp
similarity index 83%
rename from test/util/string.cpp
rename to test/str/cat.cpp
index 8ab4e81..1633f6e 100644
--- a/test/util/string.cpp
+++ b/test/str/cat.cpp
@@ -1,14 +1,10 @@
 #include <gtest/gtest.h>
-#include <stdplus/util/string.hpp>
+#include <stdplus/str/cat.hpp>
 #include <string>
 #include <string_view>
 
 namespace stdplus
 {
-namespace util
-{
-namespace
-{
 
 using namespace std::string_literals;
 using namespace std::string_view_literals;
@@ -34,6 +30,4 @@
     EXPECT_EQ("func world", strCat("func"s, " world"));
 }
 
-} // namespace
-} // namespace util
 } // namespace stdplus