added section about changed config files

docs/PLATFORMS.md

@@ -1,13 +1,14 @@
 ### Supported platforms and how to add new platforms for scraping
 
-Get a list of supported platforms with `Skyscraper --help` 
+Get a list of supported platforms with `Skyscraper --help`
 
 After the initial PR from torresflo @ GitHub it is possible to add new platforms
 by editing the `platforms.json` file. Since version 3.9.0 onwards this file is
 replaced by `peas.json` (short for platforms, extensions/formats, aliases and
 scrapers) in the same folder.
 
 Take this example from the `peas.json`:
+
 ```json
     [...]
     "megadrive": {
@@ -32,17 +33,17 @@ Take this example from the `peas.json`:
     [...]
 ```
 
-- `megadrive`: this key reflects the platform/folder name (or more generally the
-  handle), usually provided with `-p` on the command line.
-- `aliases`: these aliases can be used to allow additional hits for a search.
-  The use of aliases is handy especially for scraping websites which do _not_
-  provide a web API. Currently Screenscraper, Mobygames or The Games DB are
-  providing an web API. See also section about `platforms_idmap.csv` below.
-- `formats`: set of ROM file extensions which will be included in scraping if
-  a ROM file is not provided explicitly via command line.
-- `scrapers`: Denotes the possible scrapers if not overridden by `-s` command
-  line flag. Will be deprecated in some later versions as it is not used in the
-  codebase.
+-   `megadrive`: this key reflects the platform/folder name (or more generally the
+    handle), usually provided with `-p` on the command line.
+-   `aliases`: these aliases can be used to allow additional hits for a search.
+    The use of aliases is handy especially for scraping websites which do _not_
+    provide a web API. Currently Screenscraper, Mobygames or The Games DB are
+    providing an web API. See also section about `platforms_idmap.csv` below.
+-   `formats`: set of ROM file extensions which will be included in scraping if
+    a ROM file is not provided explicitly via command line.
+-   `scrapers`: Denotes the possible scrapers if not overridden by `-s` command
+    line flag. Will be deprecated in some later versions as it is not used in the
+    codebase.
 
 **Note**: If you need a specific folder name for a platform (on your setup or
 due to an EmulationStation theme) use a symbolic link (see `megadrive` (folder)
@@ -98,7 +99,7 @@ However, if you have local changes in these files you can transfer your local
 changes to the new files. The new `peas.json` is the `platforms.json` but in a
 more compact form which has less visual overhead and also allows faster parsing.
 The `platforms_idmap.csv` maps the former `screenscraper.json` platform ids plus
-the platform ids of two more web API sites. 
+the platform ids of two more web API sites.
 
 Use the script `convert_platforms_json.py` (sibling to the Skyscraper
 executable) to convert the `platforms.json` to a `peas_mine.json` which you can
@@ -108,3 +109,19 @@ Use the script `check_screenscraper_json_to_idmap.py` to identify differences
 from your `screenscraper.json`. Then use the three `<scraper>_platforms.json`
 files to identify the matching platform ids to be entered in
 `platform_idmap.csv`. Use `-1` if there is no matching platform id.
+
+#### Summary of changes in the config files
+
+Filenames shown ~~strikethrough~~ are superseeded.
+Filenames shown _italic_ are user editable.
+
+| File                     | Introduced        | Notes (version)                                                                                                                                      |
+| ------------------------ | ----------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- |
+| ~~`mobygames.json`~~     | 3.8.0             | superseeded by `mobygames_platforms.json` (v3.9.0); not to be edited; IDs are used in `platforms_idmap.csv`                                          |
+| ~~`platforms.json`~~     | 3.7.7-2 (@detain) | superseeded by _`peas.json`_ (3.9.0); do edit to add new platforms; uses leaner format than `platforms.json`                                         |
+| _`platforms_idmap.csv`_  | 3.9.0             | maps the platform names (handles) from _`peas.json`_ to exact platform IDs used in Moby, Screenscraper or TGDB; do edit to add new platforms         |
+| ~~`screenscraper.json`~~ | 3.7.7-2 (@detain) | IDs formerly used in here are part of `platforms_idmap.csv` (3.9.0); superseeded by `screenscraper_platforms.json` (3.9.0) which is not to be edited |
+| `tgdb_developers.json`   | 2.5.3 (@muldjord) | uses leaner format (3.9.0); not to be edited                                                                                                         |
+| `tgdb_genres.json`       | 3.9.0             | uses leaner format (3.9.0); not to be edited                                                                                                         |
+| `tgdb_platforms.json`    | 3.9.0             | uses leaner format (3.9.0); not to be edited; IDs are used in `platforms_idmap.csv`                                                                  |
+| `tgdb_publishers.json`   | 2.5.3 (@muldjord) | uses leaner format (3.9.0); not to be edited                                                                                                         |