Fix some bad merge that got the string "5.1-bugteam" into this 5.0 tree.

.bzr-mysql/default.conf:
  1) Thou shalt not have a team tree designation in this file.
  
  2) Thou shalt not claim "5.1" in a "5.0" tree.

.bzr-mysql/default.conf

 [MYSQL]
 post_commit_to = "commits@lists.mysql.com"
 post_push_to = "commits@lists.mysql.com"
-tree_name = "mysql-5.1-bugteam"
+tree_name = "mysql-5.0"