Add re-entrancy support / multiple instances (#9)

* done with changes but now segfaulting

* fixed the bug

* fix some bad indents

* some cleanings

* updated readme

demo/multipart_tx/Makefile

@@ -1,11 +1,12 @@
 CFILES=../utils.c ../../TinyFrame.c
 INCLDIRS=-I. -I.. -I../..
-CFLAGS=-O0 -ggdb --std=gnu99 -Wno-main -Wall -Wextra $(CFILES) $(INCLDIRS)
+CFLAGS=-O0 -ggdb --std=gnu99 -Wno-main -Wall -Wno-unused -Wextra $(CFILES) $(INCLDIRS)
+
+
+build: test.bin
 
 run: test.bin
 	./test.bin
 
-build: test.bin
-
 test.bin: test.c $(CFILES)
 	gcc test.c $(CFLAGS) -o test.bin