add job canceling and improve starting of jobs

SHDP-115
bonus - more utilities method (such as extracting a job state)
improve job status querying

add integration test for starting and killing jobs

SHDP-116
SHDP-115
improve Cascading tasklet/runner to share common functionality

SHDP-115
SHDP-122
add integration test for killing batch jobs

SHDP-115
SHDP-121
retrofit jobtasklet to handle batch job cancellation

SHDP-115
SHDP-121
improve job shutdown procedure

SHDP-115
SHDP-121
CascadingTasklet is aware of batch job cancellation

SHDP-115
SHDP-122
Merge branch 'shdp-115'
expose if needed, Batch StepContext to underlying threads

SHDP-115
SHDP-121
add proper registration/cleanup of batch stepcontext

SHDP-115
SHDP-121
improve CascadingTasklet when shutting down

SHDP-115
SHDP-122
upgrade gradle props plugin to 0.0.3 release