Move PrettyTables.jl to weakdeps (#439)

Closes #429

Author: ronisbr

Project.toml

@@ -9,7 +9,6 @@ CodeTracking = "da1fd8a2-8d9e-5ec2-8556-3022fb5608a2"
 FlameGraphs = "08572546-2f56-4bcf-ba4e-bab62c3a3f89"
 InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
 OrderedCollections = "bac558e1-5e72-5ebc-8fee-abe8a469f55d"
-PrettyTables = "08abe8d2-0d0c-5749-adfa-8a2ac140af0d"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 Profile = "9abbd945-dff8-562f-b5e8-e1ebf5ef1b79"
 Serialization = "9e88b42a-f829-5b0c-bbe9-9e923198166b"
@@ -19,6 +18,7 @@ YAML = "ddb6d928-2868-570f-bddf-ab3f9cf99eb6"
 [weakdeps]
 Cthulhu = "f68482b8-f384-11e8-15f7-abe071a5a75f"
 # JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
+PrettyTables = "08abe8d2-0d0c-5749-adfa-8a2ac140af0d"
 PyPlot = "d330b81b-6aea-500a-939a-2ce795aea3ee"
 
 [sources]