Add removable-media snap interface

[NathanaelGandhi]

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Description of Change

Add the removable-media snap interface. Gives snap users the option to manually connect the interface, allowing read/write access to mounted removable storage in /media, /run/media and /mnt. Interface is connected using snap connect ferdium:removable-media

Motivation and Context

• Bug/Enhancement: Cannot upload content / Add removable-media connection [snap only] #202

Checklist

• My pull request is properly named
• The changes respect the code style of the project (electron-builder formatting)
• I previewed my changes locally (formatting similar to existing)

Release Notes

Add removable-media snap interface

[NathanaelGandhi]

@vraravam This is a similar PR to #215. Interface added in the same format as existing. Ready for review & merge.

[SpecialAro]

LGTM!

[vraravam]

@all-contributors please add @NathanaelGandhi for code

[allcontributors]

@vraravam

I've put up a pull request to add @NathanaelGandhi! 🎉