labels: added basic save/read tests
labels: add label implementation
labels: added read label implementation
labels: supply operation to call on label save
labels: supply /nodes suffix to node label reader
labels: removed erroneous line from plural label runner
labels: fixed type in plural labeller
labels: added test for labelling/reading more than one node
labels: test application of multiple labels
labels: added test for replace option on writing labels
labels: implement replace option when writing labels
labels: add test for reading labels of a node
labels: implemented reading labels for a node
labels: added test for reading labels of more than one node
batching: recursively transform arguments. closes #128
labels: read labels for more than one node
labels: add test for reading all labels
labels: implement reading all labels
labels: added test for removing a label from a node
labels: implemented removing a label from a node