change writing initialized state for backward compatibility
test changes for semaphore
add missing null-value omission logic (#1019)
Merge pull request #1091 from ispringer/issue-1019

add missing null-value omission logic (#1019)
state in class javadoc that null keys and values are not allowed
add missing null key/value checks to putAll() impl; remove un-needed null value check from 2-param putAsync() (4-param putAsync() will handle the check)
add javadoc to all methods that take keys or values as params stating an NPE is thrown for null keys or values
Fixes issue #1056
Merge pull request #1094 from pveentjer/fix/maintenance-3.x/1056

Fixes issue #1056
Added missing import statements to getting started documentation
Merge pull request #1098 from pveentjer/improvement/3.maintenance/gettingstarted-documentation

Added missing import statements to getting started documentation
Initial work on locating the portable bytearray bug
Fix #1096

Fixes an issue with portable serialization resulting in different byte arrays. The cause
was a bytearray which wasn't cleaned correctly.
Merged pull #1100. Added some complex portables to test.
fix issue #1068
fix issue #1068 cont
fixes #1070
Merge pull request #1108 from enesakar/maint-issue1070

fixes issue #1070
Merge pull request #1104 from ahmetmircik/3.x

fix issue #1068
Async invocations should not be blocked on waiting backups.