DRM-102 introduce phpunit
DRM-103  include composer and phpunit into travis
DRM-103 test system configuration
DRM-104 add code-sniffer and php-compatibility as vendors
DRM-105 skip integer value in column prepare
DRM-105 consider possibility of primary_keys emptiness
DRM-107 phpdoc interfaces with @abstract tag
Merge branch 'release/0.1.1'