regress grpc to 1.6.6 (#2750)

1.7.1 causes a sigsegv in the docker container

Signed-off-by: Dave Kelsey <[email protected]>

Author: Dave Kelsey

packages/composer-connector-hlfv1/package.json

@@ -45,7 +45,7 @@
     "fabric-ca-client": "1.0.2",
     "fabric-client": "1.0.2",
     "fs-extra": "1.0.0",
-    "grpc": ">=1.3.5 <2.0.0",
+    "grpc": ">=1.3.5 <1.7.0",
     "semver": "5.3.0",
     "temp": "0.8.3",
     "thenify-all": "1.6.0",