YAML as a drop-in replacement for libconfig

This commit introduces a substitute module library for setting up softmodems using YAML instead of libconfig.
The softmodems should work the same with both types of files. Extra care was put to make sure the behavior
of both modules is the same.

Example yaml config files were added for the UE and gNB

cmake_targets/tools/build_helper

@@ -589,8 +589,9 @@ check_install_oai_software() {
 	libtool  \
 	patch \
 	openssl \
-        zlib1g-dev \
-        xxd
+	zlib1g-dev \
+	xxd \
+	libyaml-cpp-dev
 
   elif [[ "$OS_BASEDISTRO" == "fedora" ]]; then
     if [[ "$OS_DISTRO" == "rhel" ]] || [[ "$OS_DISTRO" == "centos" ]] || [[ "$OS_DISTRO" == "rocky" ]]; then
@@ -625,7 +626,8 @@ check_install_oai_software() {
       blas \
       blas-devel \
       vim-common \
-      zlib-devel
+      zlib-devel \
+      yaml-cpp-devel
   fi
 
     install_asn1c_from_source $1