janet: Update to 1.14.1

## 1.14.1 - 2021-01-18
- Add `doc-of` for reverse documentation lookup.
- Add `ev/give-supervsior` to send a message to the supervising channel.
- Add `ev/gather` and `chan` argument to `ev/go`. This new argument allows "supervisor channels"
  for fibers to enable structured concurrency.
- Make `-k` flag work on stdin if no files are given.
- Add `flycheck` function to core.
- Make `backmatch` and `backref` more expressive in pegs.
- Fix buggy `string/split`.
- Add `fiber/last-value` to get the value that was last yielded, errored, or signaled
  by a fiber.
- Remove `:generate` verb from `loop` macros. Instead, use the `:in` verb
  which will now work on fibers as well as other data structures.
- Define `next`, `get`, and `in` for fibers. This lets
  `each`, `map`, and similar iteration macros can now iterate over fibers.
- Remove macro `eachy`, which can be replaced by `each`.
- Add `dflt` argument to find-index.
- Deprecate `file/popen` in favor of `os/spawn`.
- Add `:all` keyword to `ev/read` and `net/read` to make them more like `file/read`. However, we
  do not provide any `:line` option as that requires buffering.
- Change repl behavior to make Ctrl-C raise SIGINT on posix. The old behavior for Ctrl-C,
  to clear the current line buffer, has been moved to Ctrl-Q.
- Importing modules that start with `/` is now the only way to import from project root.
  Before, this would import from / on disk. Previous imports that did not start with `.` or `/`
  are now unambiguously importing from the syspath, instead of checking both the syspath and
  the project root. This is backwards incompatible and dependencies should be updated for this.
- Change hash function for numbers.
- Improve error handling of `dofile`.
- Bug fixes in networking and subprocess code.
- Use markdown formatting in more places for docstrings.

(nia)