gtlua: implement first version of custom visitor
gtlua: implement first version of custom stream
add test cases for custom streams
add tests for custom visitor
improve error checking in gt_inlineseq tools
Merge pull request #357 from satta/lua_customstreams

Add Lua custom stream and visitor support
Merge pull request #358 from satta/inlineseq_errorcheck

improve error checking in gt_inlineseq tools
gtlua: document new Range methods
update docs
Merge pull request #360 from satta/range_docs

gtlua: add missing Range documentation
coding style
remove unnecessary header file
Merge pull request #361 from gordon/qsort

Qsort coding style and header file
do not require a sequence input
implement output buffering for GtGFF3Visitor
cosmetics
add script to check line-sortedness of GFF files
add first linesorted GFF3 out stream
add support for FASTA width and -retainids
resolve sorting