Update Containerfiles, start CLI tool.

+ Containerfiles: default to using g++.  Most of the dev machines aren't
  working with clang yet; until this is sorted out, they'll need to use
  g++.
+ Add script to determine if the git-tree is tagged.
+ Add basic CMake skeleton and start CLI tool.

is-current-tag.sh

@@ -0,0 +1,28 @@
+#!/usr/bin/env sh
+
+#########################################################################
+# @author      : kyle (kyle@imap.cc)				   	#
+# @file        : is-current-tag.sh					#
+# @created     : Wednesday Oct 18, 2023 18:36:55 PDT			#
+#									#
+# @description : determines if the current git commit is a tagged	#
+# 		 commit.						#
+#									#
+# This is used for determining whether this is a current release, and	#
+# build artifacts should be generated.					#
+#########################################################################
+
+if [ ! -z "$(git status -s)" ]
+then
+	echo "[-] work tree is dirty - not proceeding."
+	exit 0
+fi
+
+if [ -z "$(git tag --contains $(git rev-parse --verify HEAD))" ]
+then
+	echo "[-] current HEAD isn't tagged."
+	exit 0
+fi
+
+# we are in a tagged commit
+