net-im/gajim: update to 0.6.19

Changelog:

Gajim 0.16.9 (30 November 2017)

• Improve Zeroconf behavior
• Fix showing normal message event
• remove usage of OpenSSL.rand
• a few minor bugfixes

Also remove no more needed local patch that is included into
version 0.16.9

PR: 225500
Submitted by: Goran Mekić <meka@tilda.center> (based on)