Added stretches layer, removed WW-Area named. "Waterway Area, named" is no longer needed as all ww-area is coming from our db, where different sources are merged. Instead we can now display stretches. Todo: stretches for different countries should be distinguishable (different colors)

# documentation
**/README*
**/docs
**/*.md

# backend binary
cmd/gemma/gemma

# Dependency directories
**/node_modules

# local dotenv environment variables file
client/.env.local

# Tags tables
**/TAGS