Development/docs

Made small edits to the remainder of the files (5 files) in opennms-doc/guide-doc/src/asciidoc/text/. The majority of the changes were minor edits to make the text easier for native English speakers from word choice, tense and punctuation. The overall content seemed solidly written and well presented.

In one or two places a sentence was reworded to make it structurally standard and one or more sentences added to aid the clarification of a description.