[rules-dev] Last bunch of GAV changes: artifactId drools-api renamed to knowledge-api

There are a few more GAV changes. None of the directory structures needed to be changed, so the impact should be small. 1) Most notably, *the artifactId of drools-api has been renamed to knowledge-api.* This is because it contains both the drools and the jBPM api. Note: its groupId org.drools stays unaffected at this time. This impacts droolsjbpm-tools, as the lib/drools-api.jar manifest entry is now lib/knowledge-api.jar. As a result tools might need to build up to 3 times (due to the problem that tycho 0.11 will fix). 2) *Everything is set to groupId org.drools again.* The repository parent poms, introduced during the split-up, used a mixture of groupId org.drools and org.droolsjpbm. This caused more confusion that it solves, so - until we come up with a better alternative - everything is set to groupId org.drools again. Note: all actual jars never had another groupId than org.drools. -- With kind regards, Geoffrey De Smet