refactor doRequest to use a coroutine (and temporarily drop support for hhvm) (#22)

Author: shieldo

.travis.yml

@@ -1,10 +1,11 @@
 language: php
-
+sudo: required
+dist: trusty
+group: edge
 php:
     - 5.6
     - 7.0
     - 7.1
-    - hhvm
 
 matrix:
     include:

composer.json

@@ -31,7 +31,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "0.6.x-dev"
+            "dev-master": "0.7.x-dev"
         }
     }
 }