textproc/pdftohtml: Resolve conflict with poppler-utils

The conflict between this unmaintained port and poppler-utils can be
problematic. Ports should be using poppler-utils rather than this one
as a build dependency. This port's package list is 1-line long, so
lets just rename the program so that it can coexist with the version
from poppler-utils. The name changes from "pdftohtml" to "pdf-to-html"
along with a PORTREVISION bump.

Minor cleanup to pet portlint was alson done.