Support the latest built_collection and build_runner packages (#181)

Author: kevmoo

pubspec.yaml

@@ -12,15 +12,15 @@ web:
     debug: dartdevc
 
 dependencies:
-  built_collection: ^1.0.0
+  built_collection: '>=1.0.0 <3.0.0'
   built_value: '>=2.0.0 <5.0.0'
   # TODO: Move to dev_dependency in 3.0.0.
   dart_style: ^1.0.0
   matcher: ^0.12.0
   meta: ^1.0.5
 
 dev_dependencies:
-  build_runner: '>=0.4.0 <0.6.0'
+  build_runner: '>=0.4.0 <0.7.0'
   built_value_generator: '>=2.0.0 <5.0.0'
   source_gen: '^0.7.0'
   test: ^0.12.0