Restructuring project dirs and files

[a-andreyev]

Hello!
How about to separate libraries and microcoap-example folders to simplify building on both platforms?
I implemented the pull request (used actual version), changed coap to microcoap at some headers.
Also I separated enpoints header to simplify the new coap links implementing and added the info to readme file.
Changed the arduino pin from 6 to 13 (default embedded led at some arduino boards) and moved the definition to /microcoap-example/connections.h
Tested with arduino mega and with the linux-based OS.

[tobyjaffey]

I like the structure, but it doesn't compile.

cc -Wall -DDEBUG -Ilibraries/microcoap microcoap-example -c main-posix.c -o main-posix.o
clang: warning: microcoap-example: 'linker' input unused
main-posix.c:7:10: fatal error: 'coap.h' file not found
#include "coap.h"
^
1 error generated.
make: *** [main-posix.o] Error 1

[a-andreyev]

Thank you for your fast response!
Sorry for the mistakes with the previous pull request.
Does it compiles now?

For me current version is ok.