Update Ajv version to prevent spurious warnings

[andreykaipov]

This PR updates ajv@4.11.6 to ajv@5.1.0.

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When building via Webpack, there’s some spurious warnings coming from ajv -- see ajv-validator/ajv#117.

WARNING in ./~/jsoneditor/~/ajv/lib/async.js
96:20-33 Critical dependency: the request of a dependency is an expression

WARNING in ./~/jsoneditor/~/ajv/lib/async.js
119:15-28 Critical dependency: the request of a dependency is an expression

WARNING in ./~/jsoneditor/~/ajv/lib/compile/index.js
13:21-34 Critical dependency: the request of a dependency is an expression

A solution is to just add the following snippet to our webpack.config.js to ignore these warnings. This isn’t possible though if a dev is building via the Angular CLI as it actually doesn’t expose the underlying Webpack config.

plugins: [
  new webpack.IgnorePlugin(/regenerator|nodent|js-beautify/, /ajv/),
  ...
]

In the referenced issue above, the author addresses the issue was fixed in ajv@5.0.1-beta.3 (see ajv-validator/ajv#117 (comment)). Since their latest release is currently at 5.1.0 though, I've updated ajv to that.

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Tests all pass and the project still works great as before! Just no more warnings when building via Webpack or the Angular CLI now! Lemme know if I missed something!

[josdejong]

Thanks @andreykaipov . I see version 5.2.0 is already out since you opend this PR, I will update all dependencies after merging :D