feat(i18n): add ui localization

[ReenigneArcher]

Description

Add localization to UI.

I followed this guide: https://vue-community.org/vue/translating-vue-js-applications-with-vue-i18n.html

Some formatting was removed from strings, especially in config descriptions. This was done to make it both easier to translate, and easier to contribute to the source code.

Todo:

• Add remaining strings to en.json
• Determine if translations should be in /src_assets/common/assets/web/locale/ or /locale/ (2nd option is my preference... but build works as is)
• Determine if we should be using /src_assets/common/assets/web/locale/sunshine.json as the default file or /src_assets/common/assets/web/locale/en/sunshine.json (fix(i18n): allow localizing preferences page Themerr-plex#398 will be a good test of how crowdin handles this)
• Determine if the locale should be a config option or language switcher only available in the UI (decided on config option, unless there is an objection)
• Ensure localization process is documented
• Ensure build works
• How to change the language with the config value?
• html tags inside of strings dont' work. e.g. <b>SOMETHING</b>
  
• Lazy load languages https://kazupon.github.io/vue-i18n/guide/lazy-loading.html

Screenshot

Issues Fixed or Closed

• Resolves https://ideas.moonlight-stream.org/posts/353/proposal-to-implement-localization-feature-in-sunshine

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Dependency update (updates to dependencies)
• Documentation update (changes to documentation)
• Repository update (changes to repository files, e.g. .github/...)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the in code docstring/documentation-blocks for new or existing methods/components

Branch Updates

LizardByte requires that branches be up-to-date before merging. This means that after any PR is merged, this branch
must be updated before it can be merged. You must also
Allow edits from maintainers.

• I want maintainers to keep my branch updated

[ReenigneArcher]

@cgutman FYI