Added unzip binary and notes

Author: sijnstra

unzip/README.md

@@ -0,0 +1,18 @@
+# unzip
+
+Usage: <br>
+`load unzip.bin`<br>
+`run . {dir/}gzipfile {*}`<br>
+optional: run multiple times without needing to re-load unzip.bin
+
+If a destination is given, all files are extracted including directory structure.
+
+NOTES:
+<li>Spaces are not supported well in file or directory names. To avoid issues, spaces are converted to underscores.</li>
+<li>File and directory path lengths are limited to a maximum of 255 characters.</li>
+
+If not, files is checked for CRC
+
+IMPORTANT: does NOT work as MOSlet due to working memory requirements.
+
+Original unzipping core algorithms based on https://github.com/agn453/UNZIP-CPM-Z80