readme.md: correct typos, add link to command line client (#103)
readme.md: correct typos, add link to command line client (#103)

Fixed an instance of bad spelling.  Added a link to the command line client download page.
rpottsoh/xpascal,exercism/xpascal,exercism/xdelphi,rpottsoh/exercism-delphi,rpottsoh/xdelphi