Fixes #173. If pdflatex isn't present, then build() won't try to build the vignettes.
Can we do this for check() too?
Sure. But should something be done to ensure that a full check is done before a release?
Just a strongly worded warning should be sufficient. It'll be helpful for classes.
build: if pdflatex not present, don't build vignettes. Fixes #173
check_r_cmd: if pdflatex not present, don't rebuild vignettes
OK, I've made the wording a bit stronger, rebased, and added a NEWS item.
build: fix error in documentation
I think we also want to disable building the manual here too
Sure, done in 72ce098.