TARGET_PLATFORM_VERSION_MAXIMUM=4.31.0.Alpha2
JBIDE-15585: Use Tycho 0.18.1

To provide compatibility with Maven 3.1
since JBT 4.1.1.Alpha2 is now released, we can bump parent pom to 4.1.1.Beta1 & set default max TP to 4.31.1.Alpha1-SNAPSHOT
Remove some useless part of tycho-surefire-plugin configuration

With upcoming solution for Tycho Bug 386988, it doesn't make
sense to enfore product and application.
Moreover, the default values for product and application are
working fine for our test scenarios.

AFAIK, no-one is using the dependencies added, so they shouldn't
be forced by default.
JBTIS-104 use coretests site instead of integrationtests site; update TODO markers for SOA/JBTIS
JBDS-2623 jboss-requirements-composite-extras-mirror is now jboss-central-target-platform-site so update parent pom accordingly