added testfiles and installation instructions

- 6 test files can be found in testdata/S57/295K/500V/
- the README has been updated with instuctions

 On branch master
 Your branch is up-to-date with 'origin/master'.

 Changes to be committed:
	modified:   README.md
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00000.txt
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00001.txt
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00002.txt
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00003.txt
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00004.txt
	new file:   testdata/S57/295K/500V/C2S57_295k_500v00005.txt
automated creation of directories for results

- sub-directories in <outfolder> are created if needed