Fix for 906217. If replying to an email inline, and a spell check is done,

Fix for 906217.  If replying to an email inline, and a spell check is done,
spelling mistakes in the reply would be corrected on the wrong line (ie,
throughout the original email to which you are replying).  This is caused
by aspell (and possibly ispell) ignoring empty lines.

git-svn-id: https://svn.code.sf.net/p/squirrelmail/code/trunk/squirrelmail@8112 7612ce4b-ef26-0410-bec9-ea0150e637f0