Update bundler requirement from ~> 1.0 to ~> 2.0

[dependabot-preview]

Updates the requirements on bundler to permit the latest version.

Release notes

Sourced from bundler's releases.

v2.0.1

Changes:

• Relaxed RubyGems requirement to >= 2.5.0 (#6867)

Changelog

Sourced from bundler's changelog.

1.17.3 (2018-12-27)

Bugfixes:

• Fix a Bundler error when installing gems on old versions of RubyGems (#6839, @​colby-swandale)
• Fix a rare issue where Bundler was removing itself after a bundle clean (#6829, @​colby-swandale)

Documentation:

• Add entry for the bundle remove command to the main Bundler manual page

1.17.2 (2018-12-11)

• Add compatibility for bundler merge with Ruby 2.6

1.17.1 (2018-10-25)

• Convert Pathnames to Strings before sorting them, fixing #6760 and #6758 (#6761, @​alexggordon)

1.17.0 (2018-10-25)

No new changes.

1.17.0.pre.2 (2018-10-13)

Features:

• Configure Bundler home, cache, config and plugin directories with BUNDLE_USER_HOME, BUNDLE_USER_CACHE, BUNDLE_USER_CONFIG and BUNDLE_USER_PLUGIN env vars (#4333, @​gwerbin)
• Add --all option to bundle binstubs that will generate an executable file for all gems with commands in the bundle
• Add bundle remove command to remove gems from the Gemfile via the CLI
• Improve checking file permissions and asking for sudo in Bundler when it doesn't need to
• Add error message to bundle add to check adding duplicate gems to the Gemfile
• When asking for sudo, Bundler will show a list of folders/files that require elevated permissions to write to.

The following new features are available but are not enabled by default. These are intended to be tested by users for the upcoming release of Bundler 2.

• Improve deprecation warning message for bundle show command
• Improve deprecation warning message for the --force option in bundle install

1.17.0.pre.1 (2018-09-24)

Features:

• Check folder/file permissions of the Bundle home directory in the bundle doctor command (#5786, @​ajwann)
• Remove compiled gem extensions when running bundle clean (#5596, @​akhramov)
• Add --paths option to bundle list command (#6172, @​colby-swandale)
• Add base error class to gems generated from bundle gem (#6260, @​christhekeele)
• Correctly re-install gem extensions with a git source when running bundle pristine (#6294, @​wagenet)
• Add config option to disable platform warnings (#6124, @​agrim123)
• Add --skip-install option to bundle add command to add gems to the Gemfile without installation (#6511, @​agrim123)

... (truncated)

Commits

• d7ad219 Version 2.0.1 with changelog
• dc06fab Merge #6867
• 31678a3 update tested rubygems in travis
• 81d3ecf Lower required RubyGems to 2.5 or greater
• d715ae9 Bundler 2.0 with changelog
• 526bb66 update CHANGELOG with new changes and release
• 53e4ffa Merge #6856
• a0ee4cd add RubyGems v3.0.1 to rg clone task
• 00caa91 Version 2.0.0.pre.3 wih changelog
• 13ca000 update tested versions of RubyGems in travis
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Note: This repo was added to Dependabot recently, so you'll receive a maximum of 5 PRs for your first few update runs. Once an update run creates fewer than 5 PRs we'll remove that limit.

You can always request more updates by clicking Bump now in your Dependabot dashboard.

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot ignore this [patch|minor|major] version will close this PR and stop Dependabot creating any more for this minor/major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
• @dependabot use these labels will set the current labels as the default for future PRs for this repo and language
• @dependabot use these reviewers will set the current reviewers as the default for future PRs for this repo and language
• @dependabot use these assignees will set the current assignees as the default for future PRs for this repo and language
• @dependabot use this milestone will set the current milestone as the default for future PRs for this repo and language
• @dependabot badge me will comment on this PR with code to add a "Dependabot enabled" badge to your readme

Additionally, you can set the following in your Dependabot dashboard:

• Update frequency (including time of day and day of week)
• Automerge options (never/patch/minor, and dev/runtime dependencies)
• Pull request limits (per update run and/or open at any time)
• Out-of-range updates (receive only lockfile updates, if desired)
• Security updates (receive only security updates, if desired)

Finally, you can contact us by mentioning @dependabot.