7z: add page (based on 7za)

pages/common/7z.md

@@ -0,0 +1,19 @@
+# 7z
+
+> A file archiver with high compression ratio.
+
+- Compress directory or file:
+
+`7z a {{compressed.7z}} {{directory_or_file_to_compress}}`
+
+- Decompress an existing 7z file with original directory structure:
+
+`7z x {{compressed.7z}}`
+
+- Compress to zip format:
+
+`7z a -tzip {{compressed.zip}} {{directory_or_file_to_compress}}`
+
+- Create multipart 7zip file; `part_size` specifies part size in Bytes, Kilobytes, Megabytes or Gigabytes:
+
+`7z -v{{part_size}}{{[b|k|m|g]}} {{compressed.7z}} {{directory_or_file_to_compress}}`