tests are now run in sandbox underneath avatars home folder; this means files are only saved once; part of refactoring towards files not being deleted from sandbox between runs
ignore all .approvals files
ignore local backup of refactoring katas
removed 'sandbox is separate' notes from readme as it no longer is
fixed integration/reverter_tests - creating an avatar now automatically creates initial visible_files in its sandbox folder
have to delete the sandbox and recreate it on every run-tests (at the moment) so deleted files are seen as deleted
added avatar.diff_lines text in preparation for next refactoring
refactored repeated{git add X} to single{git add .}; removed unneeded parameter; renamed function
reworked the approval test so it simulates a txt file being created (that way it works if java is not installed locally)