This is a simple sentence splitter for English.
Given a string, assumed to be English text, it returns a list of strings, where
each element is an English sentence. By default, it treats occurrences of '.',
'?' and '!' as sentence delimiters, but does its best to determine when an occurrence
of '.' does not have this role (e.g. in abbreviations, URLs, numbers, etc.).
Although the splitter is designed to work for English, it should be straightforward
to adapt to other (similar) languages.