Add id global (#168)

Author: DavisVaughan

R/package.R

@@ -40,7 +40,7 @@ if(getRversion() >= "2.15.1") {
     "correlation", "correlation_mean", "directed", "dist",
     "divergence_id", "edge_id", "feature_id", "flip", "from",
     "from_milestone_id", "from_waypoint", "from2", "group_id",
-    "housekeeping", "in_divergence", "index", "input_id", "is_start",
+    "housekeeping", "id", "in_divergence", "index", "input_id", "is_start",
     "ix", "label", "length1", "length2", "milestone_id", "new_milestone_id",
     "new_new_milestone_id", "node", "node1", "node2", "num_cells",
     "one", "percentage", "PREDICT", "prior_id", "required", "rowname",