Make sorting of releases in create_release.py stable (#976)

We were only sorting by the X.Y.Z part of the version which meant that,
for example, `1.2.3` and `1.3.4-lto` were being compared equal.

emscripten-releases-tags.json

diff --git a/emscripten-releases-tags.json b/emscripten-releases-tags.json
index 8012d53..3792bae 100644
--- a/emscripten-releases-tags.json
+++ b/emscripten-releases-tags.json
@@ -17,13 +17,13 @@
     "3.1.0-asserts": "1de2db691103282dad6b2037018db6ece54f57c6",
     "3.0.1": "91b7a67a486d2430e73423a38d950d8a550826ed",
     "3.0.1-asserts": "2a84a08e92ce8748015dfc3eee40ee35a853fed0",
-    "3.0.0-asserts": "f1d65c26f502220e278d31e7621e99b673e28093",
     "3.0.0": "7fbe748230f2ce99abbf975d9ad997699efb3153",
+    "3.0.0-asserts": "f1d65c26f502220e278d31e7621e99b673e28093",
     "2.0.34": "d8fc1b92dbc0ce8d740a7adb937c5137ba4755e0",
     "2.0.33": "cef8850d57278271766fb2163eebcb07354018e7",
     "2.0.32": "74646397e3c5010824ad60d1de86c6bcbe334dff",
-    "2.0.31-asserts": "c1065389ccf4a81e3c1af080316afd444788bc46",
     "2.0.31": "597724ca3f6cd6e84bea73f1f519a3953b5c273d",
+    "2.0.31-asserts": "c1065389ccf4a81e3c1af080316afd444788bc46",
     "2.0.30": "c69458f1bbf3ef5b8da4e934de210659cc9bca04",
     "2.0.30-asserts": "e13a2d74c5fa5f175ae7cffd4197fe7f78bea304",
     "2.0.29": "c2369dc425725fff86ba90a9007a4603ddf7941b",

scripts/create_release.py

diff --git a/scripts/create_release.py b/scripts/create_release.py
index 01bf130..2d239c2 100755
--- a/scripts/create_release.py
+++ b/scripts/create_release.py
@@ -14,8 +14,10 @@
 import emsdk  # noqa
 
 
-def version_to_list(version_string):
-  return [int(part) for part in re.split('[.-]', version_string)[:3]]
+def version_key(version_string):
+  parts = re.split('[.-]', version_string)
+  key = [[int(part) for part in parts[:3]], -len(parts), parts[3:]]
+  return key
 
 
 def main(args):
@@ -24,7 +26,7 @@
     sys.exit(1)
 
   release_info = emsdk.load_releases_info()
-  new_version = version_to_list(release_info['aliases']['latest'])
+  new_version = version_key(release_info['aliases']['latest'])[0]
   new_version[-1] += 1
   branch_name = 'version_%s' % '_'.join(str(part) for part in new_version)
 
@@ -39,7 +41,7 @@
   print('Creating new release: %s -> %s' % (new_version, new_hash))
   release_info['releases'][new_version] = new_hash
   releases = [(k, v) for k, v in release_info['releases'].items()]
-  releases.sort(key=lambda pair: version_to_list(pair[0]))
+  releases.sort(key=lambda pair: version_key(pair[0]))
 
   release_info['releases'] = OrderedDict(reversed(releases))
   release_info['aliases']['latest'] = new_version