message: docs: add section about dynamically linking rocksdb
diff: @@ -51,6 +51,18 @@ sudo pacman -Sy git gcc pkgconf clang
  brew install autoconf libtool
  ```
  +### Adding Environment Variables
  +
  +If your OS contains pre-compiled `rocksdb` or `snappy` libraries,
  +you may setup `ROCKSDB_LIB_DIR` and/or `SNAPPY_LIB_DIR` environment variable
  +to point to a directory with these libraries.
  +This will significantly reduce compile time.
  +
  +```shell
  +export ROCKSDB_LIB_DIR=/usr/local/lib
  +export SNAPPY_LIB_DIR=/usr/local/lib
  +```
  +
  ### Build from source
  The `master` branch is regularly built and tested. It is always the latest released version. The default checked out branch `develop` is the latest version in development.
  