HPCC-219 Not reporting errors due to locked files

Use a new flag RTM_LOCK_HOLD to indicate locks that are held long-term, and
set it on the file locks that Roxie holds.

This should allow clients to test this lock and behave differently if set.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
HPCC-219 Not reporting errors due to locked files

Move some functions into private section of CLockInfo class, prior to minor
reworking.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
HPCC-219 Not reporting errors due to locked files

First attempt at causing locks to fail early when marked as "held".

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
HPCC-219 Not reporting errors due to locked files

Changes in response to code review.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #4095 from richardkchapman/roxie-hold-locks

Roxie hold locks

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>