Add haproxy as custom

src/haproxy.py

@@ -0,0 +1,18 @@
+import json
+import re
+import urllib.request
+
+URL = "https://www.haproxy.org/download/2.6/src/CHANGELOG"
+REGEX = r'^(\d{4})\/(\d{2})\/(\d{2})\s+:\s+(\d+\.\d+\.\d.?)$'
+
+list = {}
+with urllib.request.urlopen(URL) as response:
+  for line in response:
+    m = re.match(REGEX, line.decode('utf-8'))
+    if m:
+      year,month,date,version = m.groups()
+      abs_date = "%s-%s-%s" % (year, month, date)
+      list[abs_date] = version
+
+with open('releases/custom/haproxy.json', 'w') as f:
+  f.write(json.dumps(list, indent=2))