git repo: added files to ignore list.
rbh-recov: setting a read-only parameter (fullpath) caused request failure.
rbh-config: added new option "optimize_db" to deframent DB storage.
chglog reader: start from the last cleared record when several chglog readers are registered.

If 2 changelog readers are registered, llapi_changelog_start(with last_rec = 0)
returns the first non-acknowledged record from any reader. In this case,
robinhood re-processed the records when restarting if the other registered
readers were idle or slower.

Now, the last commited record for each MDT is saved in the VARS table.
It get this value when restarting to call llapi_changelog_start
with the last committed record.
shook: fixed mecanism for ignoring special entries.
shook: support restripe_pending status.
policies: no warning if no default policy is specified, just ignore unmatched entries.

Previously many warnings were displayed when no default policy was set.
Now, just display a notice message when starting and ignore unmatched entries
for the policy.
Added test 223 to check this behavior.
Cosmetic: display a message in Major log level when the daemon is started.

When logging with major or critical level, no message was displayed
in the log to notify the daemon started. Now it does.
backup: optionally sync data to archive on copy and free buffer cache.

Free the kernel buffer cache as we don't expect reading the files again.
This can be done immediatly for the read file.
For the writen file, it is better to flush it to disk to ensure
the file is correctly archived and to allow freeing the buffer cache.
fix build
listmgr: properly handle ER_LOCK_WAIT_TIMEOUT.

The root cause for this error is still under investigation.
However, properly handle this error when it occurs by retrying
the request.
log: changed log level for policy application start (EVENT->MAJOR).
migr/purge: increased default DB result set for policy application (10000->100000).

This results in higher performance of policy application,
as it reduces the frequency of large database requests.
rbh daemon (fix): dumping stats on SIGUSR1 caused program abort when some module were not started.

Now maintain a mask of currently running modules to dump statistics.
entryproc: added function to dump the contents of id constraint hash.
listmgr: better trace for ER_LOCK_WAIT_TIMEOUT.
fs scan: enhance the DB benchmark mode.

use various users, groups, types.
fs_scan: Fix potential deadlock on error.
entry_proc: fix DB deadlock errors. Improve default parameters for entry processor threads.

DB deadlock errors were due to simultaneous batched
requests on tables that triggered operations
on the same rows in ACCT_STAT table.
Set default behavior to batching with a single DB_APPLY thread.
To use multiple threads for DB_APPLY, batching must be disabled.
Auto-tune DB_APPLY threads when batching is disabled and
a nb_thread parameter is specified for EntryProc.
entry proc: don't insert root entry to the database.

Inserting root entry in the database result in building
a wrong path for filesystem entries from the NAMES table.
It should not be inserted. Thus, the root entry should
be ignored in the pipeline (this occurs when processing
a changelog record on it).