[crac] RFR: Handle open file descriptors with configurable policies [v9]

[Radim Vansa]

> When the application does not close some file descriptors through Resources we can use `jdk.crac.file-policy.checkpoint`, `jdk.crac.file-policy.restore`, `jdk.crac.socket-policy.checkpoint` and `jdk.crac.socket-policy.checkpoint` to configure the behaviour.
> 
> These properties can specify a list of semicolon-separated key=value pairs, where the key can be one of:
> 
> * numeric file descriptor
> * for `file-policy`, path using 'glob' pattern matching (see FileSystem.getPathMatcher() for details) - this matches named pipes, too
> * for `file-policy` keyword `FIFO` matching all pipes (including anonymous)
> * for `socket-policy` a `<local>,<remote>` pair, with the `<remote>` part being optional. Both `<local>` and `<remote>` can be unix socket path, IPv4/IPv6 address with optional colon and port number or wildcard `*` replacing any of those parts.
> 
> The possible values are in OpenFilePolicies.BeforeCheckpoint, OpenFilePolicies.AfterRestore, OpenSocketPolicies.BeforeCheckpoint and OpenSocketPolicies.AfterRestore enums.

Radim Vansa has updated the pull request incrementally with one additional commit since the last revision:

  Cosmetic fixes (imports)

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

Changes:
  - all: https://git.openjdk.org/crac/pull/69/files
  - new: https://git.openjdk.org/crac/pull/69/files/a0075b13..a245477a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=crac&pr=69&range=08
 - incr: https://webrevs.openjdk.org/?repo=crac&pr=69&range=07-08

  Stats: 34 lines in 8 files changed: 21 ins; 10 del; 3 mod
  Patch: https://git.openjdk.org/crac/pull/69.diff
  Fetch: git fetch https://git.openjdk.org/crac.git pull/69/head:pull/69

PR: https://git.openjdk.org/crac/pull/69