implemented 'koch pdf'

koch.nim

@@ -45,6 +45,7 @@ Possible Commands:
   web [options]            generates the website and the full documentation
   website [options]        generates only the website
   csource [options]        builds the C sources for installation
+  pdf                      builds the PDF documentation
   zip                      builds the installation ZIP package
   nsis [options]           builds the NSIS Setup installer (for Windows)
   tests [options]          run the testsuite
@@ -129,6 +130,10 @@ proc website(args: string) =
   exec("$# cc -r tools/nimweb.nim $# --website web/nim --putenv:nimversion=$#" %
        [findNim(), args, VersionAsString])
 
+proc pdf(args="") =
+  exec("$# cc -r tools/nimweb.nim $# --pdf web/nim --putenv:nimversion=$#" %
+       [findNim(), args, VersionAsString])
+
 # -------------- boot ---------------------------------------------------------
 
 const
@@ -351,6 +356,7 @@ of cmdArgument:
   of "clean": clean(op.cmdLineRest)
   of "web": web(op.cmdLineRest)
   of "website": website(op.cmdLineRest)
+  of "pdf": pdf()
   of "csource", "csources": csource(op.cmdLineRest)
   of "zip": zip(op.cmdLineRest)
   of "nsis": nsis(op.cmdLineRest)