pdftk: add page (#1126)

pages/common/pdftk.md

@@ -0,0 +1,23 @@
+# pdftk
+
+> PDF toolkit.
+
+- Extract pages 1-3, 5 and 6-10 from a PDF file and save them as another one:
+
+`pdftk {{input.pdf}} cat {{1-3 5 6-10}} output {{output.pdf}}`
+
+- Merge (concatenate) a list of PDF files and save the result as another one:
+
+`pdftk {{file1.pdf}} {{file2.pdf}} ... cat output {{output.pdf}}`
+
+- Split each page of a PDF file into a separate file, with a given filename output pattern:
+
+`pdftk {{input.pdf}} burst output {{out_%d.pdf}}`
+
+- Rotate all pages by 180 degrees clockwise:
+
+`pdftk {{input.pdf}} cat {{1-endsouth}} output {{output.pdf}}`
+
+- Rotate third page by 90 degrees clockwise and leave others unchanged:
+
+`pdftk {{input.pdf}} cat {{1-2 3east 4-end}} output {{output.pdf}}`