Merge pull request #2 from CHOIJAEHONG1/hotfixes/es-1.2.1

Hotfixes/es 1.2.1
fix #3
[maven-release-plugin] prepare release elasticsearch-dataformat-1.2.0
[maven-release-plugin] prepare for next development iteration
fix #4
remove javadoc lint
[maven-release-plugin] prepare release elasticsearch-dataformat-1.3.0
[maven-release-plugin] prepare for next development iteration
Update README.md
Merge remote-tracking branch 'codelibs/master' into hotfixes/sxssf_xlsx

Conflicts:
	pom.xml
	src/main/java/org/codelibs/elasticsearch/df/content/xls/XlsContent.java