OT/J quick fixes

Specific quick fixes are available for mending OT/J-related problems, including:
class modifiers
– missing team modifier,
– illegal modifier for a role,
– reducing the visibility from an (explicitly or implicitly) inherited role,
– abstract relevant role.
modifiers of methods and method bindings
– mismatch between a method's callin modifier and a callin binding's modifier (before/after/replace),
– static/non-static incompatibility in a callin replace binding,
– mismatching override of callin vs. regular role methods,
– missing callin binding modifier (before/after/replace).
inferred callout
– materializing inferred callout bindings (OTJLD § 3.1(j), § 3.5(h))
callin precedence
– missing callin precedence declaration (OTJLD § 4.8).
typing
– add a missing anchor for the type of an externalized role (OTJLD § 1.2.2, § 9.2) (proposals are infered from the context),
– adding missing final modifier to a variable used as a type anchor,
– adding required type parameter to a callin binding capturing covariant base methods(OTJLD § 4.9.3).
coding style
– change import to "import base ...",
– migrate syntax for externalized role from "anchor.R" to "R<@anchor>".
Additionally, some standard Java quickfixes and content assists have been extended to be applicable for OT/J elements, too.
suppress warnings
@SuppressWarnings annotations can be added to method bindings, too.
create method
– applies to unresolved method specs in callout/callin bindings, too.
organize imports
– creates "import base ...", if appropriate