docs: use --external for add/run

Per iterative/dvc#3929

content/docs/command-reference/add.md

@@ -6,7 +6,8 @@ Track data files or directories with DVC, by creating a corresponding
 ## Synopsis
 
 ```usage
-usage: dvc add [-h] [-q | -v] [-R] [--no-commit] [-f <filename>]
+usage: dvc add [-h] [-q | -v] [-R] [--no-commit] [--external]
+               [-f <filename>]
                targets [targets ...]
 
 positional arguments:
@@ -98,6 +99,9 @@ This way you bring data provenance and make your project
   when ready to commit outputs with DVC. This is analogous to using `git add`
   before `git commit`.
 
+- `--external` - allow targets that are outside of the DVC project. See
+  [Managing External Data](/doc/user-guide/managing-external-data).
+
 - `-f <filename>`, `--file <filename>` - specify name of the DVC-file it
   generates. This option works only if there is a single target. By default the
   name of the generated DVC-file is `<target>.dvc`, where `<target>` is the file

content/docs/command-reference/run.md

@@ -11,7 +11,7 @@ usage: dvc run [-h] [-q | -v] [-d <path>] [-o <path>] [-O <path>]
                [-w <path>] [--no-exec] [--overwrite-dvcfile]
                [--no-run-cache] [--no-commit]
                [--outs-persist <path>] [--outs-persist-no-cache <path>]
-               [--always-changed]
+               [--always-changed] [--external]
                command
 
 positional arguments:
@@ -183,6 +183,9 @@ data pipeline (e.g. random numbers, time functions, hardware dependency, etc.)
   > Note that DVC-files without dependencies are automatically considered
   > "always changed", so this option has no effect in those cases.
 
+- `--external` - allow outputs that are outside of the DVC project. See
+  [Managing External Data](/doc/user-guide/managing-external-data).
+
 - `-h`, `--help` - prints the usage/help message, and exit.
 
 - `-q`, `--quiet` - do not write anything to standard output. Exit with 0 if no

content/docs/user-guide/managing-external-data.md

@@ -52,8 +52,9 @@ The default local cache location is `.dvc/cache`, so there is no need to specify
 it explicitly.
 
 ```dvc
-$ dvc add /home/shared/mydata
+$ dvc add /home/shared/mydata --external
 $ dvc run -d data.txt \
+          --external \
           -o /home/shared/data.txt \
           cp data.txt /home/shared/data.txt
 ```
@@ -68,10 +69,11 @@ $ dvc remote add sshcache ssh://[email protected]:/cache
 $ dvc config cache.ssh sshcache
 
 # Add data on SSH directly
-$ dvc add ssh://[email protected]:/mydata
+$ dvc add ssh://[email protected]:/mydata --external
 
 # Create the stage with external SSH output
 $ dvc run -d data.txt \
+          --external \
           -o ssh://[email protected]:/home/shared/data.txt \
           scp data.txt [email protected]:/home/shared/data.txt
 ```
@@ -86,10 +88,11 @@ $ dvc remote add s3cache s3://mybucket/cache
 $ dvc config cache.s3 s3cache
 
 # Add data on S3 directly
-$ dvc add s3://mybucket/mydata
+$ dvc add s3://mybucket/mydata --external
 
 # Create the stage with external S3 output
 $ dvc run -d data.txt \
+          --external \
           -o s3://mybucket/data.txt \
           aws s3 cp data.txt s3://mybucket/data.txt
 ```
@@ -104,10 +107,11 @@ $ dvc remote add gscache gs://mybucket/cache
 $ dvc config cache.gs gscache
 
 # Add data on GS directly
-$ dvc add gs://mybucket/mydata
+$ dvc add gs://mybucket/mydata --external
 
 # Create the stage with external GS output
 $ dvc run -d data.txt \
+          --external \
           -o gs://mybucket/data.txt \
           gsutil cp data.txt gs://mybucket/data.txt
 ```
@@ -122,10 +126,11 @@ $ dvc remote add hdfscache hdfs://[email protected]/cache
 $ dvc config cache.hdfs hdfscache
 
 # Add data on HDFS directly
-$ dvc add hdfs://[email protected]/mydata
+$ dvc add hdfs://[email protected]/mydata --external
 
 # Create the stage with external HDFS output
 $ dvc run -d data.txt \
+          --external \
           -o hdfs://[email protected]/home/shared/data.txt \
           hdfs fs -copyFromLocal \
                             data.txt \