v0.6.15

• Fixed key_func error caused by free operation ( #19 )
• Fixed full name error when reading sequence without whitespace in names ( #19 )
• Fixed a hidden bug in fasta/q iteration when reading attributes (not seq)
• Fixed fasta/fastq size and sequence count error on Windows when parsing large file
• Fixed zlib 2gb and 4gb limit on windows x64 to support large file
• Reduced seek point span size to speedup random access from gzip file