cache: print cache for easier debugging

[emranemran]

It's nice to see print the cache contents when things are stored/deleted from the cache - makes debugging certain situations easier.

[codecov]

Codecov Report

Merging #76 (86806ee) into main (dfffccd) will increase coverage by 0.49988%.
The diff coverage is 100.00000%.

@@                 Coverage Diff                 @@
##                main         #76         +/-   ##
===================================================
+ Coverage   38.76543%   39.26531%   +0.49988%     
===================================================
  Files             18          18                 
  Lines           1215        1225         +10     
===================================================
+ Hits             471         481         +10     
  Misses           688         688                 
  Partials          56          56                 

Impacted Files	Coverage Δ
cache/segmenting.go	77.77778% <100.00000%> (+3.58423%)	⬆️
cache/transcoding.go	60.25641% <100.00000%> (+2.72216%)	⬆️

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Impacted Files	Coverage Δ
cache/segmenting.go	77.77778% <100.00000%> (+3.58423%)	⬆️
cache/transcoding.go	60.25641% <100.00000%> (+2.72216%)	⬆️

[thomshutt]

We should definitely print information about what's happening (Storing to / removing from the cache) and I don't love this "Debug" flag. Let's just be bold and log it until we hit traffic levels where the logging volume is an issue

[emranemran]

Updates:

• address comments
• added pretty module for pretty printing cache tables -- I was hesitant to add yet another package but the benefits of being able to grasp info from noisy logs outweighed the negatives.

"add catalyst_vod_cdegbgfe: SegmentingCache"
{catalyst_vod_cdegbgfe: {SourceFile:            "s3+https:/REDACTED/10s.mp4",
                         CallbackURL:           "https://webhook.site/12345678",
                         UploadURL:             "s3+https:/REDACTED/10s.mp4/vod/test.m3u8",
                         AccessToken:           "1234",
                         TranscodeAPIUrl:       "https://origin.livepeer.com/api/",
--
"remove catalyst_vod_cdegbgfe: SegmentingCache"
{}