Problem :
If you see any if the following error while loading the module like :
Unable to load/find moduleActivator: 'org.openmrs.module.basicmodule-parent.MyFirstActivator'

Solution :
Go to the <module omod file> 's pom.xml file and replace the following :
<MODULE_ID>${project.parent.artifactId}</MODULE_ID>
with the following
<MODULE_ID>${artifactId}</MODULE_ID>

Resources :
1.https://wiki.openmrs.org/display/IRC/2011-06-14+-+OpenMRS#133857
2.https://wiki.openmrs.org/display/IRC/2011-06-06+-+OpenMRS#190718
3.https://wiki.openmrs.org/display/IRC/2011-05-18+-+OpenMRS#170414