Minor fix when undefined CONST

Merge pull request #4 from Artem-Panasenko/6.5/RT-1807-keep-alive-curl

RT-1807 Fix bug when undefined constant

Add keep-alive options to Curl

Merge pull request #3 from Artem-Panasenko/6.5/RT-1807-keep-alive-curl

RT-1807 Add option to curl

v0.2.7

Merge pull request #2 from Tobur/master

Added to support TLS 1.2

Rj fork

Merge pull request #1 from Tobur/master

Update composer.json