Dependencies update

[sashadev-sky]

Fixes #0000 (<=== Add issue number here)

• Incorporates some of the dependency updates in Incorporate EXIF functionality (and some refactors) #169 but updates them / builds on them

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changes:

• move exif-js, webgl-distort, and glfx to dependencies
• move leaflet to peerDependencies
• move grunt-cli to devDependencies .. wasn't positive about this one but looked through Github to see what other repos do and that seems to be the consensus
• convert jQuery code to native DOM in DistortableImage.Edit.js. I don't think we need to have jQuery as a dependency in this library so removing some of it now. Will remove the rest after exporting is fixed and then remove jQuery dependency.
• update README installation instructions
• update travis.yml
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[sashadev-sky]

@rexagod I took the dependency update chunk out of your EXIF PR (#169), updated it, and made some other changes. Let me know if this is ok to merge!

[rexagod]

LGTM! 🙌