Introduce dynamic manual instructions by value setting from transformation context

[fabiocarvalho777]

Currently every manual instruction document is static. Allow the usage of transformation context attributes to set portions of manual instruction document via interpolation, by replacing placeholders in the document with values from transformation context attributes.

API changes

Notice the addAtribute method call. The first parameter, "appName", is the placeholder key in the document text, to be replaced by the value of the specified transformation context attribute (the second parameter).

add(new ManualInstruction("Fix invalid Maven dependency versions issues", "MavenEnforcer.md").executeIf(validationFailed).addAttribute("appName", APP_NAME));