Add support for understanding the Spring YML (YamlPropertiesFactoryBean) way of parsing YML files via the Archaius endpoints. This supports the ConfigProxy and PropertyRepository as these all are eventually backed by AbstractConfig.

This enables all existing Archaius read methods to read multi-line/multi-property maps and arrays as specified by Spring.

Spring YML files are converted to configs from this yml file

test:
    map:
        key1: 1
        key2: 2
        key3: 3
    stringList:
        - a
        - b
        - c

To these configs:

test.map.key1=1
test.map.key2=2
test.map.key3=3
test.stringList[0]=a
test.stringList[1]=b
test.stringList[2]=c