Add copyasstring method to MCError

Copies the contents of the error as a StringRef.
Method MCUIDC::delaymessage now takes StringRef arguments

Arguments converted from const char* to StringRef.
Update opensslsocket.cpp to remove calls to MCParameter::setbuffer
Replace calls to MCParameter::setbuffer in player.cpp
Merge branch 'refactor-syntax_unicode_setbuffer' of https://github.com/runrevfraser/livecode into refactor-syntax_unicode_setbuffer
[[ UnicodifyError ]] Changed copyasstring to copyasstringref for consistency with elsewhere.