convert: only get history for requested revs when converting hg repo

convert: raise correct type of exception if svn converter can't handle rev

record: raise an exception correctly if we can't create a backup directory

record: work properly if invoked in a subdirectory

convert: replace fork with subprocess call.

convert: support windows SVN simple auth provider

merge with crew-stable

Update on pull -u when heads were closed (fixes issue666). Patch written by Benoit Boissinot. This should probably be improved in the future to handle long-living branches, as joining two "other" heads will switch to that new head. But this is not a new problem, as adding to the "other" head would have switched to that new head, too.

gitweb: add notfound template

Add message to test output if a test is aborted due to a timeout. Without this an aborted test could produce an empty .err file so the diff looks like as if all lines of the .out files are just missing for some unknown reason.