Merge pull request #65 from nromanen/krivorotenko

Merge
Merge pull request #66 from nromanen/master

Merge
Lazy init genres. some changes
Merge branch 'yurembo' of https://github.com/nromanen/ch018 into yurembo
Merge pull request #67 from nromanen/yurembo

Yurembo
Validation Book. some changes. Bug fix
Merge pull request #68 from nromanen/yurembo

Validation Book. some changes. Bug fix
Merge pull request #69 from nromanen/master

Merge