Octstr functions do too many allocations

Hi List,

If you use mmsc and ppg performance issues are actually relevant,
because use have three protocol *suites* running in the machine.
(In spite of the fact that smsc and the wireless network are slow,)

Worst is octstr_append, used by compilers. Octstr_append_char
actually allocates just two bytes ! (Every time it is called.)

When compiling, we actually can make a guess how big the output
is, because we have the input document. So we can allocate
everything we need at the start.

Some other ideas ?

Aarno