Upgrade to mySQL5.7, Ruby warning reductions, .md file updates

[sashadev-sky]

references #347, #345

Make sure these boxes are checked before your pull request is ready to be reviewed and merged. Thanks!

• tests pass -- rake test
• code has been rebased on top of latest master (check if another pull request was added recently, and please rebase)
• pull request is descriptively named and, if possible, multiple commits squashed if they're smaller changes

Thanks!

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Points that I bolded I would like some confirmation on:

Notes on mySQL update

• update docker-compose image name
• add a MYSQL.md file with setup instructions for macOS - encourage others to write the instructions for their systems maybe open up new issues for that
• bump gem 'mysql2', '~> 0.3.20' -> gem 'mysql2', '< 0.4'

Notes on Ruby Warnings (unrelated to mySQL update)

• File.exists? (deprecated since ruby 2.2.0) updated to File.exist? everywhere in repo but made little impact almost all of them come from gems and from the source code for running a rake test. Source code is updated to File.exist? for Rails 4. Current recommendation: turn off warnings
• WARN: tilt autoloading 'sass' in a non thread-safe way; explicit require 'sass' suggested.: added a require to the sass gem in the gemfile to create an explicit require call
• URI.encode obsolete -> replaced with .to_param in repo
  • same as URI.escape obsolete error (they are alias methods) but this error is not in our repo it is in gems

Misc

• delete mapknitter/config/initializers/new_rails_defaults.rb
• Update suggested Ruby version in README
• Update recaptcha link in README
• Update PR template
• Small syntax fixes to remove warnings

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[sashadev-sky]

@coderjolly would you be able to pick a time to go over the macOS setup instructions with me really quick? I already have everything installed so these could be off need a 2nd person to look!

[sashadev-sky]

@jywarren I haven't gone through everything yet but a lot of these errors come from gems so they might be there for a while. Instead I made a file test_unit.rake with automated rake tasks for all of the unit and functional tests with the option to suppress warnings. Please let me know your thoughts on it! They can be connected for travis tests as well

[grvsachdeva]

Hey @sashadev-sky, really awesome work, sorry haven't gone through the PR closely. I can review it on Friday(busy with exams rn).

I guess, as barnraising is over, @jywarren will be back soon. Thank you!

[sashadev-sky]

@gauravano no problem good luck!

[grvsachdeva]

Thank you!

[jywarren]

This is really epic, @sashadev-sky !!!!! Amazing! Just a few small Qs and we're fine to merge this!

[sashadev-sky]

@jywarren thank you!! I still have not added the ability to set them up with Travis, I was waiting on some feedback first (do we want it to run with Travis instead of the default tests?)

[jywarren]

I believe we're aiming for MK to run on whatever we have configured in the Docker container, as we'll be increasingly treating that as the standard. So if it runs in Travis, we should be good on Mysql versions!

[sashadev-sky]

@jywarren Ok there is no version specified in the docker container for mysql as far as I can see. Does it just run with whatever it finds locally installed in the terminal session? @icarito please advise if you know!

all Rake Test Task related things have been moved into PR #380 so discussion over that here can be closed now. 👍

[sashadev-sky]

@jywarren so after moving the rake test tasks into a different PR there isn't a lot else going on here, just a clean up mostly (see PR description). Do you think this is ready for merge? Couldn't find any macOS takers to test out the mysql instructions but I figure that'll work itself out as more people start contributing

[jywarren]

Yes, this looks super. Thanks! Merging!!!