Support for VCFv4.2 + updated documentation

git-svn-id: https://svn.code.sf.net/p/vcftools/code@899 19d466ce-640d-45be-954f-fad4d9839663
Fixed a memory leak in a new output function

git-svn-id: https://svn.code.sf.net/p/vcftools/code@900 19d466ce-640d-45be-954f-fad4d9839663
Update to documentation layout in trunk.

git-svn-id: https://svn.code.sf.net/p/vcftools/code@901 19d466ce-640d-45be-954f-fad4d9839663
Update to documentation layout in trunk. (minor)

git-svn-id: https://svn.code.sf.net/p/vcftools/code@902 19d466ce-640d-45be-954f-fad4d9839663
Update to documentation layout in trunk. (minor)

git-svn-id: https://svn.code.sf.net/p/vcftools/code@903 19d466ce-640d-45be-954f-fad4d9839663
Merge remote-tracking branch 'upstream'