[OBSEQ] Add ssobuf.h for efficient 'dynamic' arrays
[OBSEQ] Add ssobuf.h for efficient 'dynamic' arrays

This avoids mallocs by keeping enough space for a single element, and
invoking malloc only when needed.

Change-Id: I696bad9316eb3780d24d415b1d012c9b72cb4e59
Reviewed-on: http://review.couchbase.org/46472
Reviewed-by: Subhashni Balakrishnan <7129c8e37b832c7bd362ff375532d24b98ef5162@gmail.com>
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

senthilkumaranb/libcouchbase,signmotion/libcouchbase,kojiromike/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,maxim-ky/libcouchbase,kojiromike/libcouchbase,maxim-ky/libcouchbase,avsej/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,maxim-ky/libcouchbase,mody/libcouchbase,kojiromike/libcouchbase,senthilkumaranb/libcouchbase,avsej/libcouchbase,couchbase/libcouchbase,signmotion/libcouchbase,signmotion/libcouchbase,senthilkumaranb/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,couchbase/libcouchbase,signmotion/libcouchbase,couchbase/libcouchbase,avsej/libcouchbase,mody/libcouchbase,couchbase/libcouchbase,PureSwift/libcouchbase,PureSwift/libcouchbase,kojiromike/libcouchbase,senthilkumaranb/libcouchbase,PureSwift/libcouchbase,couchbase/libcouchbase,PureSwift/libcouchbase,mody/libcouchbase,maxim-ky/libcouchbase,mody/libcouchbase