Update README.md

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Merge pull request #39 from mstssk/patch-1

Update README.md
operation mistake
Merge branch 'release/1.6.3'
Merge branch 'release/1.6.3' into develop
operation mistake... http://central.sonatype.org/pages/apache-maven.html
1.6.5
Merge branch 'release/1.6.4'
Merge branch 'release/1.6.4' into develop
1.6.6
update maven-release-plugin 2.4.1 to 2.5
Merge branch 'release/1.6.6'
prepare
:scream_cat:
Merge branch 'master' into release/1.6.7

Conflicts:
	jsonpullparser-apt/pom.xml
	jsonpullparser-core/pom.xml
	jsonpullparser-google-http-client/pom.xml
	jsonpullparser-parent/pom.xml
	pom.xml
Merge branch 'release/1.6.7'
Merge branch 'master' of github.com:vvakame/JsonPullParser
Merge branch 'master' into develop

Conflicts:
	jsonpullparser-apt/pom.xml
	jsonpullparser-core/pom.xml
	jsonpullparser-google-http-client/pom.xml
	jsonpullparser-parent/pom.xml
	pom.xml