Fixes/ruby 2 2 syntax error

[etagwerker]

Hey @jnraine,

This is an attempt to fix #13. Unfortunately it seems that it will generate a spec failure:

$ bundle exec rspec spec

DeprecationTracker
  #add
    groups messages by bucket
    ignores messages when bucket null
    transforms messages before adding them
  #compare
    ignores buckets that have no messages
    raises an error when recorded messages are different for a given bucket
  #save
    saves to disk
    combines recorded and stored messages
    overwrites stored messages with recorded messages with the same bucket
    sorts by bucket
    sorts messages
  DeprecationTracker::KernelWarnTracker
    captures Kernel#warn (FAILED - 1)
    captures Kernel.warn (FAILED - 2)

TenYearsRails
  has a version number

Failures:

  1) DeprecationTracker DeprecationTracker::KernelWarnTracker captures Kernel#warn
     Failure/Error: expect(warn_messages).to eq(["oh", "no"])

       expected: ["oh", "no"]
            got: []

       (compared using ==)
     # ./spec/deprecation_tracker_spec.rb:206:in `block (3 levels) in <top (required)>'

  2) DeprecationTracker DeprecationTracker::KernelWarnTracker captures Kernel.warn
     Failure/Error: expect(warn_messages).to eq(["oh", "no"])

       expected: ["oh", "no"]
            got: []

       (compared using ==)
     # ./spec/deprecation_tracker_spec.rb:218:in `block (3 levels) in <top (required)>'

Finished in 0.04994 seconds (files took 0.24047 seconds to load)
13 examples, 2 failures

Failed examples:

rspec ./spec/deprecation_tracker_spec.rb:197 # DeprecationTracker DeprecationTracker::KernelWarnTracker captures Kernel#warn
rspec ./spec/deprecation_tracker_spec.rb:209 # DeprecationTracker DeprecationTracker::KernelWarnTracker captures Kernel.warn

I'm not sure what's the best way to fix that issue. It's probably related to dropping activesupport as a dependency. Any thoughts about that?

Thanks!

[etagwerker]

@jnraine thanks for your help! I just pushed the changes we worked on. Let me know if there is anything else that could be improved. 👍

[etagwerker]

@jnraine just a gently reminder about this PR, do you think this is good to go? 😄

[etagwerker]

@jnraine I had missed a couple of problems (like using named parameters) -- I just pushed a couple more changes to fix problems running this gem with older ruby versions.

[mctaylorpants]

Closing; see #17 (comment) for more context.