remove implicit mapping to first sequence

Accepts the use of '-encseq', '-seqfile' and '-seqfile'
without '-matchdesc' or '-usedesc' only when MD5 tagged
annotations are used.
add gt_strand_invert()
fix strand output in ORF finder
ensure return to silence compiler warnings
Merge pull request #210 from satta/regionmap-options

remove implicit mapping to first sequence
Merge pull request #212 from satta/orf-strand

Fix ORF finder strand output