Fixed TIMESTAMDIFF for PostgreSQL

• fixed PostgreSQL implementation of TIMESTAMPDIFF function to match results returned by MySQL implementation

Apply PSR2 standard

1.1.1

Merge branch '1.0' into 1.1

Apply PSR2 standard

Merge pull request #35 from orocrm/cs

Check PSR2

Replace function

• Replace function added
• updated build test matrix, added maria db, percona db, latest versions of mysql and postgresql, dropped support of PHP 5.3

Note!
Starting this release new features will be with minor version change

MD5 Function

• Added MD5 string function support

GROUP_CONCAT fix

Fixed issue #19

CAST to boolean

• added support for cast to boolean
• fixed cast of negative values
• added build for posgresql 9.4
• fixed YAML component version

CAST to JSON

Added CAST to JSON on supported platforms, for others will be casted as string

CONCAT_WS

Added CONCAT_WS support

CAST improvements

Merge pull request #9 from orocrm/ticket/BAP-8368_refactoring

BAP-8368: Refactoring CAST function