sqBodywrap was extreme slow on large messages. The reason for that were the

sqBodywrap was extreme slow on large messages. The reason for that were the
amount of calls to sq_strpos and sq_substr. Those functions did expensive
in_array calls and a few other things that only need to be done once. By
using static vars I cached the results with as result my compose screen
opens within a second again instead of 10 seconds.

git-svn-id: https://svn.code.sf.net/p/squirrelmail/code/trunk/squirrelmail@11788 7612ce4b-ef26-0410-bec9-ea0150e637f0