Refactored metadata management
* Metadata belonging to different functionality areas (i.e. common, hiv) now in separate classes
* Moved constants into same file as installation
Merge branch 'master' of github.com:I-TECH/openmrs-module-kenyaemr

Conflicts:
	api/src/main/java/org/openmrs/module/kenyaemr/Metadata.java
	api/src/main/java/org/openmrs/module/kenyaemr/metadata/MchMetadataProvider.java
	api/src/test/java/org/openmrs/module/kenyaemr/metadata/MetadataPackagesTest.java
Fixes after previous faulty merge
Removed metadata package content that's now installed via provider classes
* Completely removed forms package
* Core package now only has patient identifiers and a provider
* Added integration unit test which loads all providers and refreshs the form and program managers
Fixed NPE in program-content fragment when a program doesn't have any visit forms
Moved patient identifiers from metadata package to their respective provider classes
Identifiers table in admin section now indicates if identifier type is required
* Also replaced some literal text values with message codes
upstream changes
metadata ===> mchMetadata