refactor: Not needed dependencies removed/moved to peerDependencies

[muratcorlu]

• I think aws-lambda added to dependencies by mistake. Removed it
• reflect-metadata mentioned in Readme file to be installed separately. That means it should be a peerDependency. Moved it.
• install-self-peers expecting yarn to be installed. yarn is not a dependency. I preferred to run it via npm.

ps: build command is also needs yarn, now. I couldn't find npm equivalent of yarn cache. But I thinks it's also wise to build project with npm.