Better build/dev scripts

README.md

client/src/app/core/auth/auth-user.model.ts

client/src/app/core/auth/auth.service.ts

client/src/app/videos/video-watch/video-watch.component.ts

package.json

scripts/build.sh

scripts/build/client.sh

scripts/build/server.sh

scripts/dev/client.sh

scripts/dev/server.sh

scripts/watch/client.sh

scripts/watch/server.sh

support/doc/client/code.md

support/doc/server/code.md

yarn.lock