Set application/link-format to ID 40 as per RFC7252

CoAP has been assigned RFC7252. In doing so, the CoAP Content-Formats Registry has also assigned an official value of 40 for application/link-format.
update README (add link to lualwm2m)
added isMarkLastRequestFailed 
extended LinkObject
improved code and added some tests
fix register/deregister server sent event bug.
remove consoleLog
fix multi-instance problem
add licence on js/css
#27: Reading individual resources assumes text/plain
#28: No content format when writing objects
add support of read for multi instance resource
#5: missing license header on js/html/css files
bootstrap server is a standalone server now
started like the device management server
license headers
A REST API for the bootstrap server

The first /api/bootstrap is for reading and
writing bootstrap configurations
Merge remote-tracking branch 'origin/master' into osgi-module

Conflicts:
	leshan-core/src/main/java/leshan/server/lwm2m/client/LinkObject.java
	pom.xml