Release 0.1.8

• add Pack3r version number to pk3/zip comment field
• fix stale lightmap/stylelightshader logging wrong day count
• add log hint about --loose when files are missing
• add -v None to pack without printing
• log where missing files were referenced in
• fix missing "source only" flag on remapped misc_model shaders
• log if creating a pk3 deletes/overwrites an existing file
• delete benchmark project
• fix wrong order when "downcasting" from tga to jpg
• add shaderlist support for pk3s
• add tests for tga/jpg integrity checks
• disable parsing parallelization when debugging
• use QPath and QString types internally to simplify comparisons and sorting