Update cheatsheets

pbmmake

@@ -0,0 +1,17 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# pbmmake
+
+> Create a blank bitmap.
+> More information: <https://netpbm.sourceforge.net/doc/pbmmake.html>.
+
+- Create a blank bitmap of the specified dimensions:
+
+`pbmmake {{width}} {{height}} > {{path/to/output_file.pbm}}`
+
+- Specify the color of the created bitmap:
+
+`pbmmake -{{white|black|grey}} {{width}} {{height}} > {{path/to/output_file.pbm}}`