convert to CMake.

CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.15)
+project(ke C)  # Specify C language explicitly
+
+set(CMAKE_C_STANDARD 99)
+set(KE_VERSION "0.9.3")
+
+# Add executable
+add_executable(ke main.c)
+
+# Define KE_VERSION for use in C code (e.g., #define KE_VERSION)
+target_compile_definitions(ke PRIVATE KE_VERSION="${KE_VERSION}")
+
+# Set output properties
+set_target_properties(ke PROPERTIES
+        FOLDER bin
+        RUNTIME_OUTPUT_DIRECTORY bin
+)