Plugin Template updates

[imhoffd]

The following can be addressed before the feature freeze:

• the CLI prompt recommends a class name suffix of Plugin, which results in a PluginPlugin suffix for web
• class names are inconsistent between native and web "I entered MyPlugin and that created a plugin that's accessible via Capacitor.Plugins.MyPlugin" (moved to Plugin Template updates for 3.0 #3267)
• Podspec has a bunch of whitespace issues
• rollup.config.json is present, but rollup is neither installed nor configured (also should be updated to use the new node-resolve)
• provide an initial separation between functionality and bridge communication (see Capacitor v3: Make plugins usable for native code #3222) (moved to Plugin Template updates for 3.0 #3267)
• Provide prettier, swiftlint etc. and whatever the Capacitor Community settles on for consistent tooling (cc @priyankpat)
• strict mode, strict mode, strict mode! and clean up tsconfig.json

[ionitron-bot]

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