do_count.c(): Add call tracing
do_count.c(): Add call tracing

The added tracing is enabled by uncommenting out this line:
//#define DO_COUNT_TRACE

Trace example:
linkparser> This is a test
  do_count:542 lw=-1 rw=6 le=(nil) re=(nil) null_count=1
    do_count:315 lw=0 rw=6 le=RW re=(nil) null_count=0
      do_count:433 lw=0 rw=5 le=hWV re=(nil) null_count=0
        do_count:433 lw=0 rw=2 le=Wd re=Ss null_count=0
          do_count:433 lw=0 rw=1 le=(nil) re=(nil) null_count=0
          return(C):433=1
          do_count:446 lw=1 rw=2 le=(nil) re=(nil) null_count=0
          return(C):446=1
          do_count:465 lw=1 rw=2 le=Ss*b re=Ss null_count=0
          return(C):465=0
        return(C):433=1
...

ampli/link-grammar,linas/link-grammar,linas/link-grammar,linas/link-grammar,opencog/link-grammar,linas/link-grammar,ampli/link-grammar,opencog/link-grammar,opencog/link-grammar,opencog/link-grammar,linas/link-grammar,linas/link-grammar,opencog/link-grammar,opencog/link-grammar,linas/link-grammar,linas/link-grammar,linas/link-grammar,ampli/link-grammar,ampli/link-grammar,ampli/link-grammar,ampli/link-grammar,ampli/link-grammar,opencog/link-grammar,opencog/link-grammar,ampli/link-grammar,ampli/link-grammar,opencog/link-grammar