cleanup lints and changelog (#31)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f8c9e75..0a63c4a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,11 +1,7 @@
 ## 2.0.0
 
 - Stable null safety release.
-
-## 2.0.0-nullsafety.0
-
-- Upgrade to sound null safety.
-- Require Dart 2.12.0-0.
+- Require Dart 2.12.0.
 
 ## 1.0.3
 
diff --git a/analysis_options.yaml b/analysis_options.yaml
index 9ac56b5..89fc0e8 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -6,30 +6,21 @@
 
 linter:
   rules:
-    - always_declare_return_types
-    - annotate_overrides
     - avoid_bool_literals_in_conditional_expressions
     - avoid_catching_errors
     - avoid_classes_with_only_static_members
+    - avoid_dynamic_calls
     - avoid_empty_else
     - avoid_function_literals_in_foreach_calls
-    - avoid_init_to_null
-    - avoid_null_checks_in_equality_operators
     - avoid_private_typedef_functions
     - avoid_redundant_argument_values
-    - avoid_relative_lib_imports
     - avoid_renaming_method_parameters
-    - avoid_return_types_on_setters
     - avoid_returning_null
     - avoid_returning_null_for_future
     - avoid_returning_null_for_void
     - avoid_returning_this
-    - avoid_shadowing_type_parameters
-    - avoid_single_cascade_in_expression_statements
-    - avoid_types_as_parameter_names
     - avoid_unused_constructor_parameters
     - avoid_void_async
-    - await_only_futures
     - camel_case_types
     - cancel_subscriptions
     - cascade_invocations
@@ -37,8 +28,6 @@
     - constant_identifier_names
     - control_flow_in_finally
     - directives_ordering
-    - empty_catches
-    - empty_constructor_bodies
     - empty_statements
     - file_names
     - hash_and_equals
@@ -46,72 +35,43 @@
     - invariant_booleans
     - iterable_contains_unrelated_type
     - join_return_with_assignment
-    - library_names
-    - library_prefixes
     - lines_longer_than_80_chars
     - list_remove_unrelated_type
     - literal_only_boolean_expressions
     - missing_whitespace_between_adjacent_strings
     - no_adjacent_strings_in_list
-    - no_duplicate_case_values
     - no_runtimeType_toString
     - non_constant_identifier_names
-    - null_closures
-    - omit_local_variable_types
     - only_throw_errors
     - overridden_fields
     - package_api_docs
     - package_names
     - package_prefixed_library_names
-    - prefer_adjacent_string_concatenation
     - prefer_asserts_in_initializer_lists
-    - prefer_collection_literals
-    - prefer_conditional_assignment
     - prefer_const_constructors
     - prefer_const_declarations
-    - prefer_contains
-    - prefer_equal_for_default_values
     - prefer_expression_function_bodies
-    - prefer_final_fields
     - prefer_final_locals
     - prefer_function_declarations_over_variables
-    - prefer_generic_function_type_aliases
     - prefer_initializing_formals
-    - prefer_inlined_adds
     - prefer_interpolation_to_compose_strings
-    - prefer_is_empty
-    - prefer_is_not_empty
     - prefer_is_not_operator
     - prefer_null_aware_operators
     - prefer_relative_imports
-    - prefer_single_quotes
     - prefer_typing_uninitialized_variables
     - prefer_void_to_null
     - provide_deprecation_message
-    - recursive_getters
-    - slash_for_doc_comments
     - sort_pub_dependencies
     - test_types_in_equals
     - throw_in_finally
     - type_annotate_public_apis
-    - type_init_formals
-    - unawaited_futures
     - unnecessary_await_in_return
-    - unnecessary_brace_in_string_interps
-    - unnecessary_const
-    - unnecessary_getters_setters
     - unnecessary_lambdas
-    - unnecessary_new
     - unnecessary_null_aware_assignments
     - unnecessary_overrides
     - unnecessary_parenthesis
     - unnecessary_statements
     - unnecessary_string_interpolations
-    - unnecessary_this
-    - unrelated_type_equality_checks
-    - use_function_type_syntax_for_parameters
     - use_is_even_rather_than_modulo
-    - use_rethrow_when_possible
     - use_string_buffers
-    - valid_regexps
     - void_checks