Add CMake File (#101)

* CMakeLists file for building a QCBOR library

* Adding compiler flag
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..8a5bcd0
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 3.10.2)
+project(qcbor
+	DESCRIPTION "QCBOR"
+	LANGUAGES C
+	VERSION 1.0.0)
+
+set(CMAKE_C_FLAGS "-pedantic -Wall -O3 -ffunction-sections")
+
+include_directories(inc)
+
+set(SOURCE
+	src/ieee754.c
+	src/qcbor_decode.c
+	src/qcbor_encode.c
+	src/qcbor_err_to_str.c
+	src/UsefulBuf.c
+) 
+
+add_library(qcbor ${SOURCE})