changelog: hexlify node when throwing a LookupError on a filtered node The non-hexlified node was leaking all the way out to the web interface, and wasn't consistent with the behavior for nonexistent nodes.

byterange: remove old two-arg raise trick We don't care about the original traceback, and this was frustrating any efforts to make the code work on Python 3.3.

revlog: document v0 format

merge crew heads

merge with mpm stable

templater: add get() function to access dict element (e.g. extra)

templates: export extra as a dict to templates Currently only useful with the json filter.

Added signature for changeset 7511d4df752e

Added tag 2.5.1 for changeset 7511d4df752e

merge with i18n