DOC: make mentioning of pipeline_name consistent

- we really should not advocate having '_' as a separator, so I made example to use
  'pipeline1-v1' and 'pipeline2.  This should make it much more consistent
  with how we name in BIDS where '_' is a separator between entities.
- we had <pipeline> and <pipeline_name> (as we used in other places).
  I unified to <pipeline_name> although would not mind going to <pipeline>
  or introducing (expclitly) that '<pipeline>' means '<pipeline_name>[-<variant>]'

Author: yarikoptic

src/common-principles.md

@@ -309,7 +309,7 @@ Derivatives can be stored/distributed in two ways:
     Different components of a pipeline can, however, also be stored under different
     subdirectories.
     There are few restrictions on the directory names;
-    it is RECOMMENDED to use the format `<pipeline>-<variant>` in cases where
+    it is RECOMMENDED to use the format `<pipeline_name>-<variant>` in cases where
     it is anticipated that the same pipeline will output more than one variant
     (for example, `AFNI-blurring` and `AFNI-noblurring`).
     For the sake of consistency, the subdirectory name SHOULD be
@@ -381,7 +381,7 @@ Derivatives can be stored/distributed in two ways:
 
 Throughout this specification, if a section applies particularly to derivatives,
 then Case 1 will be assumed for clarity in templates and examples, but removing
-`/derivatives/<pipeline>` from the template name will provide the equivalent for
+`/derivatives/<pipeline_name>[-<variant>]` from the template name will provide the equivalent for
 Case 2.
 In both cases, every derivatives dataset is considered a BIDS dataset and must
 include a `dataset_description.json` file at the root level (see
@@ -423,8 +423,8 @@ A guide for using macros can be found at
             "..." : "",
         },
         "derivatives": {
-            "pipeline_1": {},
-            "pipeline_2": {},
+            "pipeline1-v1": {},
+            "pipeline2": {},
             "...": "",
         },
         "dataset_description.json": "",

src/modality-agnostic-files/dataset-description.md

@@ -130,8 +130,8 @@ and a guide for using macros can be found at
 
 If a derived dataset is stored as a subdirectory of the raw dataset, then the `Name` field
 of the first `GeneratedBy` object MUST be a substring of the derived dataset directory name.
-That is, in a directory `<dataset>/derivatives/<pipeline>[-<variant>]/`, the first
-`GeneratedBy` object should have a `Name` of `<pipeline>`.
+That is, in a directory `<dataset>/derivatives/<pipeline_name>[-<variant>]/`, the first
+`GeneratedBy` object should have a `Name` of `<pipeline_name>`.
 
 Example: