use ftruncate() to resize blooms file
use ftruncate() to resize blooms file

instead of using lseek() repeatedly in a loop

(original commit by Vicent Marti, rebased and tweaked by Pierce Lopez,
any bugs added probably due to the latter)

giserh/dablooms,lenovor/dablooms,lenovor/dablooms,lenovor/dablooms,giserh/dablooms,lenovor/dablooms,tutuhuagong/dablooms,giserh/dablooms,tutuhuagong/dablooms,tutuhuagong/dablooms,ploxiln/dablooms,bitly/dablooms,tutuhuagong/dablooms,ploxiln/dablooms,giserh/dablooms,giserh/dablooms,lenovor/dablooms,bitly/dablooms,giserh/dablooms,tutuhuagong/dablooms,bitly/dablooms,ploxiln/dablooms,tutuhuagong/dablooms,lenovor/dablooms