concurrency fix
* Migrations should pause during member join & while post-join ops are running. *Query op should throw exception when target is left.
Fixed post-join proxy initialization. Added test.
Fixed map service owned partitions usage.
Added migration aware service hooks when a backup is promoted to primary replica.
Improved QueryTest.testQueryWithIndexDuringJoin()
Made the simulateload a bit nicer for demonstrations

What happened is when there are multiple threads, there is not always an equal balance of load.
Sometimes, due to timing, a threads get an additional task. So e.g. if you are doing 16 tasks
with 2 threads and each task takes 1 second, then you would expect after 8 seconds it to be
complete. The 'bug' was that sometimes it is 9 seconds. With is perfectly fine, but it sucks
for demo's. This commit fixes that problem
Merge pull request #1130 from pveentjer/fix/3.x/testapp-simulateload-syncing

Made the simulateload a bit nicer for demonstrations
added asynchronous execution capability on key with EntryProcessor
Client side test added
test for executeOnKey()
Fix return value on client side
throw exception instead of returning null value
improved implementation and tests
typo
no need to catch exception
Added a map.localSize method
Merge pull request #1114 from eminn/feature/asyncEntryProcessorOnKey

Feature/async entry processor on key
Merge pull request #1131 from pveentjer/fix/3.x/testapp-simulateload-syncing

Added a map.localSize method
Various testapp improvements

* added the map.localSize
* added enabled management center by default. It will connect to port 8080.