Adhere to naming conventions in StatementContext.

The naming convention introduced is to have the most prominent entity that the method deals with named first in the method name.
The rationale behind this is to group the methods by name, and to facilitate IDE "tab completion".

The rules applied to the names are:


 * The most prominent entity the method deals with is the first word of the method name.
 * If dealt with in general, the word is pluralized.
 * We prefer physical entities to meta-entities (e.g. node is preferred to index and label).
 * `#nodesGetFromIndexLookup(IndexDescriptor, Object)` is a good example for both of the last two rules, nodes are the physical entities we are interested in, therefore that word is first, the index is just a means of getting to the nodes.