[DOC] Improvents to index.rst
[DOC] Improvents to index.rst

* adding short summary what SeqAn is about
* fixing typo
xp3i4/seqan,JohnReid/seqan,bayolau/seqan,bayolau/seqan,hannespetur/SeqAnHTS,ktrappe/seqan,hannespetur/SeqAnHTS,limeng12/seqan,xp3i4/seqan,holtgrewe/seqan,limeng12/seqan,holtgrewe/seqan,limeng12/seqan,xp3i4/seqan,ktrappe/seqan,PF2-pasteur-fr/seqan,budach/seqan,xenigmax/seqan,xenigmax/seqan,hannespetur/SeqAnHTS,budach/seqan,limeng12/seqan,PF2-pasteur-fr/seqan,xenigmax/seqan,holtgrewe/seqan,JohnReid/seqan,JohnReid/seqan,ktrappe/seqan,bestrauc/seqan,PF2-pasteur-fr/seqan,bayolau/seqan,xp3i4/seqan,xp3i4/seqan,limeng12/seqan,xp3i4/seqan,xp3i4/seqan,JohnReid/seqan,budach/seqan,ktrappe/seqan,bayolau/seqan,hannespetur/SeqAnHTS,limeng12/seqan,bayolau/seqan,budach/seqan,hannespetur/SeqAnHTS,hannespetur/SeqAnHTS,bestrauc/seqan,catkira/seqan,limeng12/seqan,ktrappe/seqan,holtgrewe/seqan,hannespetur/SeqAnHTS,xenigmax/seqan,holtgrewe/seqan,ktrappe/seqan,bayolau/seqan,catkira/seqan,JohnReid/seqan,bayolau/seqan,JohnReid/seqan,PF2-pasteur-fr/seqan,bestrauc/seqan,catkira/seqan,JohnReid/seqan,bestrauc/seqan,xenigmax/seqan,catkira/seqan,limeng12/seqan,catkira/seqan,bayolau/seqan,bestrauc/seqan,catkira/seqan,bestrauc/seqan,budach/seqan,hannespetur/SeqAnHTS,PF2-pasteur-fr/seqan,budach/seqan,xp3i4/seqan,ktrappe/seqan,catkira/seqan,xp3i4/seqan,hannespetur/SeqAnHTS,holtgrewe/seqan,xenigmax/seqan,PF2-pasteur-fr/seqan,bestrauc/seqan,JohnReid/seqan,ktrappe/seqan,budach/seqan,PF2-pasteur-fr/seqan,PF2-pasteur-fr/seqan,xenigmax/seqan,ktrappe/seqan,catkira/seqan,PF2-pasteur-fr/seqan,limeng12/seqan,budach/seqan,xenigmax/seqan,catkira/seqan,bestrauc/seqan,JohnReid/seqan,bayolau/seqan,budach/seqan,holtgrewe/seqan,holtgrewe/seqan