rename maven artifacts for clarification (now: org.ws4d.jcoap.core, org.ws4d.jcoap.examples, org.ws4d.jcoap.proxy)
jcoap.core: removed jUnit4 dependency from classpath; was already part of maven build
jcoap.examples: removed jcoap.core project dependency from classpath; added dependency to maven build

setReadable() and isReadable() are marked as deprecated

Fixes #1 Changed Error code from "Forbidden"(403) to "Method not allowed" (405) when a resource does not accept a certain method

merged BasicResourceTest, InterfaceTest and PlugTest into a single file to avoid race condition on IP address during parallel testing phase of maven
modified some ToDos
BasicCoapSocketHandler now uses CoAP constants for multicast Socket addresses instead of strings

added plugtest tests to general jCoAP automated tests
resolved ToDos

- ResourceType is now an interface and no an abstract class

moved to maven build; changed to log4j2 aligned package structure to jcoap.core; adapt to jcoap.core changes

    - removed unnecessary lib .jars
    - changed package structure
    - moved enumerations in separate package
    - added MultiType resource to handle content types in a resource
    - moved as much fields as possible to private
    - replaced TimeoutHashMap.java by the new version
    - updated maven build configuration

Use constant for MTU in the core resource and fixed potential field hiding in the basic coap resource

 - TimeoutHashMap2 has now reduced memory footprint (~50% - removed timeque)
 - TimeoutHashMap2 is now thread save (synchronized methods & moved update of the map from Timer to TimeoutHashMap2)
 - TimeoutHashMap2 now focuses on fast insert and remove, instead of fast removal of expired entries as this happens in the background

 - TimeoutHashMap2 as alternative to TimeoutHashMap which keeps its content updated on its own by using an internal thread who wakes when an entry has timed out and deletes it.

 - CoapChannelListener.java -> empty and unused (updated CoapClient and CoapServer accordingly)
modified
 - documentation (CoapResource)
 - cleanup (CoapResponseCode, CoapRequestCode, CoapPacketType )
 - added first test setting (InterfaceTest)
 - ResourceServer Interface now extends CoapServer (instead of being parallel)
 - ToDo's: removed already finished ToDo's, added some Fixme's for potential null pointer access

CoapChannelManager & BasicCoapChannelManager - Added method to remove resource server channel from the channel manager (used to stop resource server)
BasicCoapRequest - Changed getURIPath to return non-URL-encoded string
CoapResource & BasicCoapResource - added new Constructors and setValue methods for string values instead of byte[]; Removed writable and replaced by postable & putable
Resource Server & CoapResourceServer - implemented start & stop; reviewed onRequest; updated create permissions & process
CoreResource - updated access permissions, Fixed filter query bug
BasicResourceTest & InterfaceTest - updated test setUp
Encoder - added as helper class to encode and decode UTF-8 string <-> byte[]

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Deleted:
 - CoapWellKnownResource - unfinished & unused
 - Resource - merged content into CoapResource.java -> avoids problematic casting in the ResourceServer
 - ResourceHandler - undocumented/unknown purpose & unused
Modified:
 - AbstractCoapMessage -> BUGFIX CoAP Header Option ignored
 - CoapMediaType -> added mime types
 - BasicCoapResource -> added interface description, size estimate & configuration for read and write permissions
 - CoapResource -> changed to more generic datatypes & merged with Resource
 - CoapResourceServer -> changed according to modiied interfaces
 - CoreResource -> now inherits from BasicCoapResource & removed duplicate code & added feature "/.well-known/core filter"
 - Resource Server -> changed according to modified interfaces & enhanced documentation
 - InterfaceTest -> removed encoding error & warning suppress

    - added pom.xml with dependencies
    - removed external jar files
    - moved test classes into separate folder
    - created gradle build for java and OSGI

    URI-Path segments are now limited to 255 bytes (instead of 270)
    exception will be thrown if not (on client and server side)