Adding a Rakefile to build jQuery core, for those that need it.

Rakefile

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+# Basic Rakefile for building jQuery
+files = [ "intro", "core", "data", "event", "support", "selector", "traversing", "attributes", "manipulation", "css", "ajax", "fx", "offset", "dimensions", "outro" ]
+
+date = `git log -1 | grep Date: | sed 's/[^:]*: *//'`.gsub(/\n/, "")
+version = `cat version.txt`.gsub(/\n/, "")
+
+task :default => :jquery
+
+task :jquery => [:selector] do
+	sh "mkdir -p dist"
+
+	sh "cat " + files.map {|file| "src/" + file + ".js"}.join(" ") +
+		" | sed 's/Date:./&" + date + "/' | " +
+		" sed s/@VERSION/" + version + "/ > dist/jquery2.js"
+end
+
+task :selector do
+	sh "sed '/EXPOSE/r src/sizzle-jquery.js' src/sizzle/sizzle.js > src/selector.js"
+end