Fix & in URLs to & for correctness of HTML, also 100% to "100%" in

Fix & in URLs to & for correctness of HTML, also 100% to "100%" in
table definitions.

Remove two cases of </TR></TD></TABLE> in formatBody, moving the </TR></TD>
bit back into src/read_body.php to match the <TABLE><TR><TD> before the
function call, and removing the excessive close tags problem.

The possibly controversial bit: remove all outputting of <BASE> tags within
the message body.  I refer you to:

http://www.w3.org/TR/1998/REC-html40-19980424/struct/links.html#h-12.4

specifically,

When present, the BASE element must appear in the HEAD section of an
HTML document, before any element that refers to an external source.

git-svn-id: https://svn.code.sf.net/p/squirrelmail/code/trunk/squirrelmail@2461 7612ce4b-ef26-0410-bec9-ea0150e637f0