added mcsla core

MCSLA/mcsla-core/.gitignore

MCSLA/mcsla-core/.gitlab-ci.yml

MCSLA/mcsla-core/LICENSE.txt

MCSLA/mcsla-core/README.md

MCSLA/mcsla-core/pom.xml

...eu/DECIDEh2020/mcsla/core/metrics/AggregationMaxType.java

...eu/DECIDEh2020/mcsla/core/metrics/AggregationMinType.java

...eu/DECIDEh2020/mcsla/core/metrics/AggregationSumType.java

...20/mcsla/core/metrics/AvailabilityAggregationSumType.java

.../DECIDEh2020/mcsla/core/metrics/AvailabilityMTBFMTTR.java

...20/mcsla/core/metrics/AvailabilityUptimeBillingCycle.java

...rc/main/java/eu/DECIDEh2020/mcsla/core/metrics/Empty.java

...a/eu/DECIDEh2020/mcsla/core/metrics/EvaluationResult.java

...n/java/eu/DECIDEh2020/mcsla/core/metrics/Expressions.java

...ava/eu/DECIDEh2020/mcsla/core/metrics/MetricsContext.java

...in/java/eu/DECIDEh2020/mcsla/core/metrics/Predefined.java

.../DECIDEh2020/mcsla/core/metrics/PredefinedExpression.java

...CIDEh2020/mcsla/core/metrics/ServiceObjectiveMetrics.java

...ain/java/eu/DECIDEh2020/mcsla/core/metrics/Statement.java

MCSLA/mcsla-core/src/test/resources/DECIDE.json