serve: add and use portable spawnvp replacement There is no standard python command to really detach a process under Windows. Instead we use the low level API wrapped by subprocess module with all necessary options to avoid any kind of context inheritance. Unfortunately, this version still opens a new window for the child process. The following have been tried: - os.spawnv(os.P_NOWAIT): works but the child process is killed when parent console terminates. - os.spawnv(os.P_DETACH): works on python25, hang on python26 when writing to the hgweb output socket. - subprocess.CreateProcess() hack without shell mode: similar to os.spawnv(os.P_DETACH). Fix 1/3 for issue421

shrink-revlog: help/doc tweaks - make it look right in 'hg help extensions' - clarify --revlog option - add a main program to tell users this is no longer a standalone script

Add shrink-revlog.py to win32 installer

shrink-revlog: make it work on windows (issue1976)

merge main with stable

merge crew together

merge stable together

merge with stable

shrink-revlog: avoid cryptic error when used as an extension When shrink-revlog is used as an extension, it would produce an error when switching back to stable because the script will try to execute itself.

transaction: initialize self.journal to None after deletion This avoid a warning when having an empty transaction, where hg would try to delete the journal twice.