Roll Observatory packages and add a roll script

packages/petitparser/lib/src/lisp/parser.dart

Index: packages/petitparser/lib/src/lisp/parser.dart
diff --git a/petitparser/lib/src/lisp/parser.dart b/packages/petitparser/lib/src/lisp/parser.dart
similarity index 92%
rename from petitparser/lib/src/lisp/parser.dart
rename to packages/petitparser/lib/src/lisp/parser.dart
index aa00c180b90377a20e71cffe0450cc5177a687f0..a14c2913196306f212fe74e69003317d9c3c994b 100644
--- a/petitparser/lib/src/lisp/parser.dart
+++ b/packages/petitparser/lib/src/lisp/parser.dart
@@ -1,15 +1,11 @@
-part of lisp;
+part of petitparser.lisp;
 
-/**
- * LISP parser.
- */
+/// LISP parser.
 class LispParser extends GrammarParser {
   LispParser() : super(new LispParserDefinition());
 }
 
-/**
- * LISP parser definition.
- */
+/// LISP parser definition.
 class LispParserDefinition extends LispGrammarDefinition {
 
   list() => super.list().map((each) => each[1]);