LTI 1.3 shared

This is a fork of the LTI 1.3 shared library, with no source code modification, just for convenience, to be used by Drop Project.

It can be installed using maven:

<dependency>
    <groupId>org.dropproject</groupId>
    <artifactId>lti-13-core-for-dp</artifactId>
    <version>1.0.2</version>
</dependency>