Use trusty to enable HHVM and add PHP 7.2 to the mix.

 Fix warning when selectTelegramUpdate() returns bool here

Update contact info

Do not process duplicated updates, prevent stopping the script

Update composer dependencies and fix sniffed code.

Fix empty date for User and Chat entities

Allow empty string for `switch_inline_query` parameters

Fix payment related entity relations and types.

Improve changelog to emphasise SQL migration scripts.

Bot API 3.5

Add new sendMediaGroup method

sendMediaGroup method was missing, see https://core.telegram.org/bots/api#sendmediagroup

Bot api 3.4

Correctly check for empty value, instead of using empty().

Fixes #670

Scrutinizer improvements

Refactor TelegramLog a tiny bit.

[skip ci]