v0.8: Merge pull request #49 from gmarcais/approx_header

1. Fixing the hot spot issue with distributed counter.
2. Merging pull request from gmarcais/approx_header

V0.7

1. Commenting out "fallocate" to compile on MAC OS.
2. Adding partitioned counter in the CQF code to update the metadata about the k-mer counts dynamically.
3. Minor bug fixes.

V0.6

Merge branch 'development'