- simplify (.mkdirs parent-dir) and with (io/make-parents file)
- should return false when HTTP request fails, not nil
- check if corrputed file exitsts before deleting it
- add tests

- storage-test: worker should handle other storage operations if some of
them throws Exception
- storage-test: microformats and proxied-photo should be stored as is
- microformats-test: use-prop shuold handle both string and keyword
typed keys
- comment unused http client functions

- print clear stack trace using timbre when capturing exceptions
- don't pass nil to url/normalize; if url/normalize gets a nil, instead
of NPE, it now returns an empty string
- capture exceptions in processor pipeline to keep it from dying
- http.downloader now checks response status instead of blindly
downloading anything

- add weepinbell.http.client/with-retry macro
  - retry only requests that returns :error with type TimeoutException
  - retry is done asynchronously
  - with-retry should return a Future
- retry verifier requesting source and target, 3 times with 5 seconds
backoff

- replace mf2j with mf2clj
- remove utils.clj completely
- refactored processor, use Chain of Responsibilities pattern and pass
around maps to reuse data (so we don't have to make a separate HTTP
request just to parse microformats, etc.)
- test: add more test cases to verifier test
- test: add basic test cases to all processing steps
- add more logging to each processing steps. good for debugging.

starting from now, every commit should be cljfmt-fixed

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