Release candidate 2 of version 2.0 of the SPDX Java Library

@bact

What's Changed

Fix minor typos in docstrings by @bact in #265
Bulletizes README by @bact in #267
Fix Javadoc rendering issue by @bact in #268
Issue 270 pass exception to InvalidLicenseException so root cause is in stack trace by @gabetrau in #271
Remove unnecessary warning by @goneall in #272
Fix log message by @dwalluck in #277
Fix incorrect assertion by @dwalluck in #278
Simplify append call by @dwalluck in #279
Remove unused compiler and javadoc options by @dwalluck in #276
Fix spelling by @dwalluck in #280
Add cause to runtime exception by @dwalluck in #281
Call SpdxModelFactory::init when constructing LicenseCreatorAgent by @dwalluck in #287
Add SPDX-FileCopyrightText and SPDX-FileType to source file header by @bact in #291
Add functions to return maps of licenses by @goneall in #290
Add support for storing properties of type Double by @goneall in #274
Test getId for listed licenses by @goneall in #289
Initialize default model store in init method by @goneall in #286
Vendored license list version 3.26 by @goneall in #292
Update library versions to RC2 by @goneall in #293

Full Changelog: v2.0.0-RC1...v2.0.0-RC2