Fixed issue #3037 by closing socket

Conflicts:

server/src/main/java/com/orientechnologies/orient/server/distributed/ODi
stributedResponseManager.java
Fixed issue #3057
Stack of initialized graphs was created to gracefully handle nested graph createions.
Merge branch 'develop' of github.com:orientechnologies/orientdb into develop
Stack of initialized graphs was created to gracefully handle nested graph createions.
Added support for token based authentication supported via a plugin mechanism.

Conflicts:
	core/src/main/java/com/orientechnologies/orient/core/db/ODatabase.java
	core/src/main/java/com/orientechnologies/orient/core/db/raw/ODatabaseRaw.java
	core/src/main/java/com/orientechnologies/orient/core/db/record/ODatabaseRecordAbstract.java
	core/src/main/java/com/orientechnologies/orient/core/metadata/security/OSecurityNull.java
	core/src/main/java/com/orientechnologies/orient/core/metadata/security/OSecurityProxy.java
	core/src/main/java/com/orientechnologies/orient/core/metadata/security/OSecurityShared.java
	object/src/main/java/com/orientechnologies/orient/object/db/OObjectDatabaseTx.java
	server/src/main/java/com/orientechnologies/orient/server/OServer.java
	server/src/main/java/com/orientechnologies/orient/server/network/protocol/http/OHttpRequest.java
	server/src/main/java/com/orientechnologies/orient/server/network/protocol/http/OHttpUtils.java
	server/src/main/java/com/orientechnologies/orient/server/network/protocol/http/ONetworkProtocolHttpAbstract.java
	server/src/main/java/com/orientechnologies/orient/server/network/protocol/http/command/OServerCommandAuthenticatedDbAbstract.java
Added support for token based authentication supported via a plugin mechanism.
updated to the last version of the user managment, fixed some java8 dependency
reformated jwt source code with the orient formatter
replaced base64 encoder for jwt with orient base64 encoder for avoid duplicate code.
renaming following the orient naming convention.
refactor jwt impl for allow extensions.
implemented first unit test on token handler.
add additional serialization tests.
test token forge attempt
written basic binary jwt based on web implentation