RFR: 8303784: no- at Target annotations should be applicable to type parameter declarations [v6]

[Liam Miller-Cushon]

> Please consider this fix for https://bugs.openjdk.org/browse/JDK-8303784, which make `@Target`-less annotations applicable to type parameter declarations.
> 
> `@Target`-less annotations are applicable to 'all declaration contexts', which includes type parameter declarations.

Liam Miller-Cushon has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:

 - Merge branch 'master' into JDK-8303784
 - Use Feature enum for version checks
 - Add a test case with no --release flag
 - Make fix contingent on --release 14
   
   based on discussion in CSR.
 - Move test under `test/langtools/tools/javac/annotations/typeAnnotations`
 - 8303784: no- at Target annotations should be applicable to type parameter declarations

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/12914/files
  - new: https://git.openjdk.org/jdk/pull/12914/files/749af3cc..6b03a477

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12914&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12914&range=04-05

  Stats: 495182 lines in 4948 files changed: 389506 ins; 65649 del; 40027 mod
  Patch: https://git.openjdk.org/jdk/pull/12914.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/12914/head:pull/12914

PR: https://git.openjdk.org/jdk/pull/12914