Merge pull request #251 from ReactiveBayes/graphviz_issue_233

Graphviz issue 233

Author: bvdmitri

.gitignore

@@ -55,3 +55,4 @@ statprof
 profile.pb.gz
 .swp
 *.info
+test/ext/graphviz_test_imgs

Project.toml

@@ -19,9 +19,11 @@ Unrolled = "9602ed7d-8fef-5bc8-8597-8f21381861e8"
 Cairo = "159f3aea-2a34-519c-b102-8c37f9878175"
 Distributions = "31c24e10-a181-5473-b8eb-7969acd0382f"
 GraphPlot = "a2cc645c-3eea-5389-862e-a155d0052231"
+GraphViz = "f526b714-d49f-11e8-06ff-31ed36ee7ee0"
 
 [extensions]
 GraphPPLDistributionsExt = "Distributions"
+GraphPPLGraphVizExt = "GraphViz"
 GraphPPLPlottingExt = ["Cairo", "GraphPlot"]
 
 [compat]
@@ -32,6 +34,7 @@ Dictionaries = "0.4"
 Distributions = "0.25"
 Documenter = "1.0"
 GraphPlot = "0.5, 0.6"
+GraphViz = "0.2"
 MacroTools = "0.5"
 MetaGraphsNext = "0.6, 0.7"
 NamedTupleTools = "0.14"