Add regression test for teleporting between neighbouring regions on the same simulator

This adds a non-advertised wait_for_callback option in [EntityTransfer].  Default is always true.
Teleport tests disable the wait for callback from the destination region in order to run within a single thread.
Remove some test code that accidentally crept in with 9d2e1c67
Comment out the five second sleep in etm.DoTeleport() if the old agent needs to be closed because it is no longer in the child's view distance.

This sleep appears unnecessary since a sleep has already occurred in WaitForCallback() whilst waiting for the destination region to notify of teleport success.
There are no async operations between this sleep and the WaitForCallback()
If this sleep is present, then teleporting back to the source region within 5 seconds results in a disconnection.
If this sleep is commented out then teleporting quickly back and forth between two simulators appears to work without issue.
Tested on standalone, local grid and distributed grid.
Please revert if there's something that I've missed.
Implement optional name and description on http stream handlers so that we can relate a slow request to what the handler actually does and the agent it serves, if applicable.

This is most useful for capabilities where the url is not self-describing.
minor: resolve some mono compiler warnings
Remove the somewhat misleading logging of the string length of some unknown requests, as this appeared to be some kind of numbered error code.

This brings these messages into line with similar messages that did not do this.
Fixes Mantis #5999. llSetLinkPrimitiveParams with PRIM_BUMP_SHINY did cause a runtime error.
Reinsert a 2000ms delay before closing a no longer required agent on the source region after teleport to resolve Imprudence teleport problems.

Viewers 1 and 3 are fine with doing this immediately.  However, Imprudence has a small delay (<200ms, >500ms) after receiving the AgentCompleteMovement reply packet on the destination region before regarding that region as the currnet region.
If Imprudence receives a DisableSimulator in this period, it quits.
We are not restoring the full 5000ms delay since this brings back a bug where teleports permanently fail if an avatar tries to teleport back too quickly.
This commit also sends the AgentCompleteMovement packet to the client before telling the source region to release its old agent, in order to further cut down any possibility of the DisableSimulator being recieved before the AgentMovementComplete.
Merge branch 'master' of ssh://opensimulator.org/var/git/opensim
Extend 'slow' request logging to other server outbound requests (forms, rest, async rest) as well as the existing logging on outbound OSD requests.

Also prints out the first 100 chars of any slow request data since this can contain useful info (such as agent ID).
minor: Tweak BaseHttpServer message to make it clear that this relates to slow handling of inbound requests.
Calculate the Daylight Savings Time information sent to the viewer based on US Pacific Standard Time rather than whatever timezone the login server is set to.

This is because the viewer doesn't receive a timezone from the server but bases its displays on Pacific Standard Time.
However, it still expects to receive notification from the server as to whether or not Daylight Savings Time for PST is in operation.
This commit introduces a new DSTZone setting in the [LoginService] config setting that accepts a list of timezone names valid across different platforms to calculate Pacific DST.
If you need the old behaviour of calculating DST based on the local timezone of the server running the login service, then please override DSTZone with "local".
A mailing list announcement will be made later.
Thanks to Olivier Van Helden and Gudule Lapointe for determining this behaviour and providing this patch.
From http://opensimulator.org/mantis/view.php?id=5972
Allow deleting folders even if they're not in the Trash

The functions DeleteFolders() and PurgeFolder() still work as before, i.e. they only allow deleting folders that are in the Trash. However, the functions DeleteFoldersEx() and PurgeFolderEx() can now be used to delete any folder.
refactor: Rename new DeleteFoldersEx/PurgeFoldersEx methods to DeleteFolders/PurgeFolders overloads as previously discussed with Oren - I think this makes more sense on balance

These overloads are not publicly available on core connectors or IInventoryService.
Change LongCallTime on WebUtil to 3000, to match the time where request handling is considered "slow".

This may be the wrong thing to do but stops lots of log spam in HG setups now that the monitoring is extended to other outgoing calls.
LongCallTime may need to be made configurable.
Mantis 60004 problems with damage and llSetDamage. In damage enabled areas this patch - Deletes any objects that have damage set > 0 that deliver that damage to an avatar Stops Gods receiving damage, Stops volume detect objects causing damage Deletes NPCS when their helth reduces to zero Gradually "heals" damage to an avatar Resets health on going to a non damage area
minor: remove mono compiler warning
Temporarily add debug log lines to lsl url request and release

To help with http://opensimulator.org/mantis/view.php?id=5993
Don't try and update the access time of a file that is actively being cached.

This may cause IOErrors on Windows.
Aims to help with http://opensimulator.org/mantis/view.php?id=6003
Use the more efficient HashSet instead of List for FlotasmAssetCache.m_CurrentlyWriting