Rework compat features into breaking changes

This reverses polarity and makes things easier to explain

Author: mandolaerik

deprecations_to_md.py

@@ -6,25 +6,26 @@
 [path_to_dml, header, outfile] = sys.argv[1:]
 sys.path.append(path_to_dml)
 
-from dml import breaking_changes as compat
+from dml import breaking_changes
 from dml.env import api_versions, default_api_version
 
 by_version = {}
-for feature in compat.features.values():
-    if (feature.last_api_version.str in api_versions()
+for feature in breaking_changes.changes.values():
+    if (feature.required_after.str in api_versions()
         # don't document features that are unconditionally disabled in
         # this Simics version
-        or feature.last_api_version > compat.apis[default_api_version()]):
-        by_version.setdefault(feature.last_api_version, []).append(feature)
+        or feature.required_after > breaking_changes.apis[default_api_version()]):
+        by_version.setdefault(feature.required_after, []).append(feature)
 
 with open(outfile, 'w') as f:
     f.write(Path(header).read_text())
     for (ver, features) in sorted(by_version.items()):
         f.write(fr"""
-### Features available up to and including -\-simics-api={ver.str}
-These features correspond to functionality removed when compiling using
+### Changes for migrating from -\-simics-api={ver.str}
+These changes are enabled automatically when compiling using
 Simics API {ver.ordinal + 1} or newer. With older Simics API versions, these
-features can be disabled individually by passing <tt>-\-no-compat=<em>TAG</em></tt>
+features can be disabled individually by passing
+<code>-\-breaking-change=<em>TAG</em></code>
 to the `dmlc` compiler.
 """)
         f.write("<dl>\n")