Changes

     -o  defines the out file which and has the STDOUT set as the default.

     -o  defines the out file which and has the STDOUT set as the default.

         vt recognizes the appropriate output by file extension.

         vt recognizes the appropriate output by file extension.

         <name>.vcf - uncompressed VCF

         <name>.vcf     - uncompressed VCF

         <name>.vcf.gz  - compressed VCF

         <name>.vcf.gz  - compressed VCF

         <name>.bcf - BCF

         <name>.bcf     - BCF

         You may modify the STDOUT to output the binary version of the format.  Uncompressed

         You may modify the STDOUT to output the binary version of the format.  Uncompressed

         VCF and BCF streams are indicated by - and + respectively.   

         VCF and BCF streams are indicated by - and + respectively.