[Pharo-dev] [Reflectivity] AST Link Annotation Infrastructure

Hi, For review: https://pharo.fogbugz.com/f/cases/15026/Link-installation-infrastructure-for... <https://pharo.fogbugz.com/f/cases/15026/Link-installation-infrastructure-for...> This provides the infrastructure to annotate the AST nodes with “MetaLinks”. -> when the first link set in a method, the twin is created -> when the last is removed, the twin is destroyed to not waste space. testUninstallLink | sendNode link | sendNode := (ReflectivityExamples>>#exampleMethod) ast body statements first value. link := MetaLink new. sendNode link: link. (ReflectivityExamples>>#exampleMethod) class = ReflectiveMethod. link uninstall. self assert: (ReflectivityExamples>>#exampleMethod) class = CompiledMethod. self assert: (ReflectivityExamples>>#exampleMethod) reflectiveMethod = nil. Marcus