Add absolute minimal example

dev/VisualStudio/main.c

@@ -11,7 +11,7 @@
  * \return          `ch` value on success, `0` otherwise
  */
 int
-lwprintf_output(int ch, struct lwprintf* lw) {
+lwprintf_output(int ch, lwprintf_t* lw) {
     printf("%c", (char)ch);
     return ch;
 }

docs/examples_src/example_minimal.c

@@ -0,0 +1,19 @@
+#include "lwprintf/lwprintf.h"
+
+/* Called for every character to be printed */
+int
+lwprintf_out(int ch, lwprintf_t* lwp) {
+    /* May use printf to output it for test */
+    printf("%c", (char)ch);
+
+    return ch;
+}
+
+int
+main(void) {
+	/* Initialize default lwprintf instance with output function */
+    lwprintf_init(lwprintf_out);
+
+    /* Print first text */
+    lwprintf_printf("Text: %d", 10);
+}