Patch: fix #14

#14 anticipated difficulties with timestamp files and file targets in project subdirectories.

Use system2() not system()

That means makefile(..., command = "make --jobs=2") becomes makefile(..., command = "make", args = "--jobs=2").

Makefiles are no longer standalone!

You must call makefile(...) to run the Makefile. Do not use the command line. The reason is that makefile(...) creates dummy timestamp files so that the Makefile can see which jobs don't need to be run. As a consequence, makefile(...) needs to run an initialization step right before each time the Makefile is called. Otherwise, your build steps will be incorrect. You can just generate the Makefile without running it using makefile(..., run = FALSE).

Fix broken vignette links

v0.0.2

Complete broken sentence

Fix name ordering and point to vignette in help files.

v0.0.1

Add test files

First release

v0.0.0

Refine DESCRIPTION