Fix formatting and spelling mistakes in the documentation.

Highlights:
  - In maven-surefire-plugin/src/site/apt/developing.apt.vm, make sure text is
    not rendered bold.
  - In maven-surefire-plugin/src/site/markdown/newerrorsummary.md, ensure
    proper formatting of the list at the bottom of the page.
  - In maven-surefire-plugin/src/site/site.xml, add link to "Using POJO Tests"
    example.
  - In maven-surefire-report-plugin/src/site/fml/faq.fml, mention that
    upgrading Surefire will resolve the listed known issue.
  - Settle on a consistent title casing for (sub)headings.
  - Synchronize page titles with window titles and menu titles, where sensible.
  - Fix/make consistent italic/bold/monospace typesetting of various terms.
Remove reference to SVN