Merge commit 'tor-0.2.2.21-alpha' into debian-merge

* commit 'tor-0.2.2.21-alpha': (60 commits)
  fold in another set of changes
  add in missing changelog entries
  0.2.1.29 changelog and blurb
  fold in more changes entries
  repeat overlapping changelog entries
  bump to 0.2.2.21-alpha
  Fix a couple of non-cleared key issues in hidden services
  Zero out some more key data before freeing it
  Update the spec with the new bounds
  Tighten accepted circwindow parameters
  Provide constant limits for all consensus params
  Fix a typo spotted by Roger
  Sanity-check consensus param values
  Make get_net_param_from_list() static
  Add missing check for hostname answer_len in dnsserv size
  clean up message; explain a magic number in a comment
  make the description of tolen_asserts more dire
  Fix a heap overflow found by debuger, and make it harder to make that mistake again
  Always nul-terminate the result passed to evdns_server_add_ptr_reply
  catch another overlong malloc possibility. found by cypherpunks
  ...