merge: fix bug going backwards for already reverted files (issue1303)

churn: generalisation, now it is possible to see statistics grouped by custom template

Merge with crew-stable

Add missing catch of a TypeError

provide nicer feedback when an unknown node id is passed to a command Previously, an unknown node id would lead to the following error: abort: 00changelog.i@343445453433: no node! All other unknown revision would instead display as: abort: unknown revision '343445453'! The former error message has been suppressed in favor of the latter.

tests: check for bzr support by importing bzrlib This is better than starting bzr --version, because it works correctly when running tests with a non-default Python (version).

convert: fixed python2.3 incompatibility in bzr source (generator expression)

Improve error handling in osutil.c 1) In posix part set error when path is too long so instead of SystemError: error returned without exception set it will raise ValueError: path too long 2) In Win32 part replace generic PyErr_SetExcFromWindowsErrWithFilename by PyErr_SetFromWindowsErrWithFilename The exception returned is WinError(based on OSError) and some rudimentary errno translation is performed from Windows error range to errno module friendly range so errors like ENOENT can be handled via symbolic constant and consistently between Win32 and Posix.

`source` doesn't work for some /bin/sh, use `.` instead

fix conflicting variables when no native osutil is available thanks weijun for the bug report and patch, fix issue1309