fix javadocs errors.

M
Merge pull request #25 from msimonin/fixJavadoc

fix javadocs errors.
update changelog.

M
Merge pull request #27 from msimonin/maint-2.1.0

update changelog.
update release plugin.
[maven-release-plugin] prepare release snoozecommon-2.1.5
[maven-release-plugin] prepare for next development iteration
Merge branch 'maint-2.1.0'

Conflicts:
	pom.xml
gitignore