Bound concurrent syscalls; avoid I/O starvation EUCA-3032

- Add system.exec.restricted_concurrent_ops property
  (default: 2)
- Add system.exec.max_restricted_concurrent_ops property
  (default: 'dd,tar,gunzip')
- Restrict number of concurrent calls to anything in the list
  system.exec.restricted_concurrent_ops to no more than
  system.exec.max_restricted_concurrent_ops concurrent executions
[NC] Do not time out BOOTING instances that are in-process migrations.

Fixes EUCA-6013.
[NC] Rework semaphore handling for migrations.

Progress toward EUCA-6024.
Merge remote-tracking branch 'origin/testing' into dev/juphoff/migration
Fix EUCA-5978 Use eucalyptus admin to create euca:tags
[CC] Continue sending migration prepare requests to NCs even after failures.

Fixes EUCA-6055.
EUCA-6017 changed upgrade to add a new property for 'cloud.monitor.default_poll_interval_mins' from 'reporting.monitor.default_poll_interval_mins' and set the value type of this type from long to Long
changed from an add/delete item to just an update (needed field name) for EUCA-6017
Changed since property from v_3_2_2 v_3_3_0 to update reporting.default_poll_interval_mins to cloud.monitor.default_poll_interval_mins (EUCA-6017)
Auto scaling scaling flag now set for instance replacement - EUCA-6077

Terminate instances activity now sets the scaling flag when necessary to
ensure replacement instances are launched reliably. This was causing a
failure to replace unhealthy instances if the first launch attempt
failed for the replacement.

EUCA-6077
EUCA-6017 changed upgrade to rename the configuration property 'reporting.monitor.default_poll_interval_mins' to 'cloud.monitor.default_poll_interval_mins' and set the value type of this type from long to Long
Merge branch 'dev/ethomas/EUCA-6017-3' into dev/ethomas/EUCA-6017-3-merge
EUCA-6087
Fixing icons and tooltips, addressing the block device mapping problems.
Maintenance-mode bug-fixing.

- [NC] Don't automatically clean up instance if libvirt domain lookup
       fails--may be a migration anomaly.
- [NC] Track active outgoing-migration count, don't rollback timed-out
       migration preparations if they're being blocked due to an active
       migration.
- [NC] Don't deauthorize client credentials on migration destination
       if there are still pending (but not yet active) migrations.
- [NC] Don't blank migration src & dst information in instance struct
       on source when rolling back; the information is useful elsewhere.
- [NC] Refactor migration key generation into separate function.
- [NC] Verify in-progress migration counter when refreshing instance
       info.
- [NC] Don't time out preparing migrations when other outgoing
       migrations are in progress.
- [NC] Don't regenerate migration credentials when unchanged from
       previously used credentials (i.e. part of a multi-instance
       migration).
- Ignore Emacs auto-save files.

Progress toward EUCA-6024, EUCA-6030.
Merge branch 'dev/juphoff/migration' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/migration
Merge branch 'dev/juphoff/migration' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/migration
Merge remote-tracking branch 'origin/testing' into dev/juphoff/migration

Conflicts:
	node/handlers.c
	node/handlers_kvm.c
[NC] Fix merge-conflict resolution of call to find_and_terminate_instance().

Fixes EUCA-6024.
Merge remote-tracking branch 'origin/testing' into dev/juphoff/migration

Conflicts:
	node/handlers.c
	node/handlers_kvm.c
re-indent