1.0.0 Release Candidate 1 of the SPDX Java model 2

What's Changed

• SPDX Document Verify and message updates by @goneall in #5
• Allow any protocol in URLs by @goneall in #7
• Updates for RC1 by @goneall in #8

Full Changelog: v0.1.0-Alpha...v1.0.0-RC1

Initial Release of the SPDX Java Model 2.X

Most of these model file originated from the pre-2.0 version of the SPDX Java Library.

This is the first release of the library with the 2.X version of the model supplied in an independent Java JAR file.