inotify: improve error messages
* prefix messages by inotify-(client|server)
* make sure that all warning and abort messages use the same format.
* in the case where inotify.sock is an old broken symlink, say so and abort
instead of trying to overwrite the already existing link
% create test repository
adding a
adding b
adding c
% churn separate directories
user1 1 ***************************************************************
% churn all
user3 3 ***************************************************************
user1 3 ***************************************************************
user2 2 ******************************************
% churn up to rev 2
user2 2 ***************************************************************
user1 1 ********************************
% churn with aliases
alias3 3 **************************************************************
alias1 3 **************************************************************
user2 2 *****************************************
% churn with .hgchurn
alias3 3 **************************************************************
alias1 3 **************************************************************
user2 2 *****************************************
% churn with column specifier
user3 3 ***********************
user1 3 ***********************
user2 2 ***************
% churn by hour
06 1 *****************
09 2 *********************************
12 4 ******************************************************************
13 1 *****************
% churn with separated added/removed lines
user1 +3/-1 +++++++++++++++++++++++++++++++++++++++++--------------
user3 +3/-0 +++++++++++++++++++++++++++++++++++++++++
user2 +2/-0 +++++++++++++++++++++++++++
% changeset number churn
user1 4 ***************************************************************
user3 3 ***********************************************
user2 2 ********************************
adding foo
test 0