[maven-release-plugin] prepare release v1.5.1
[maven-release-plugin] prepare release v1.5.1

mtmse/nordic-epub3-dtbook-migrator,nlbdev/nordic-epub3-dtbook-migrator,nlbdev/nordic-epub3-dtbook-migrator,mtmse/nordic-epub3-dtbook-migrator,nlbdev/nordic-epub3-dtbook-migrator,mtmse/nordic-epub3-dtbook-migrator,nlbdev/nordic-epub3-dtbook-migrator,mtmse/nordic-epub3-dtbook-migrator