tcl.minor default

[jordansread]

for #437

I ended up doing this in a way that isn't testable except for the result of the render...

This is because I don't want the fraction of par('tcl') to be calculated until it is relevant - i.e., when the side is being rendered, so it is stuck into the draw_axis w/ the arg = NA signifying to use this default. It is buried from the user, but the alternative solution that covers this and was discussed in #437 with the hierarchy is too complex for the value of this functionality. Additional thoughts welcome.

[lindsayplatt]

Since it's not testable except for rendering, did you build any of the vignettes? I imagine we would see a change because the tcl.minor default was 0.15 and should now be -0.25 if par('tcl') remains unchanged.

I think having NA carry through to the final gsplot object makes sense to me. People can just look in the documentation to figure out what the actual value should be since it could change if pars change.

[jordansread]

@lindsaycarr the tcl is in the default config already as 0.3. I will keep that as-is. Working on merge conflicts for the vignettes now and that is coming w/ the next commit.

[jordansread]

changes in the vignettes all seem to be due to the retina screen render. Note we don't have anything in the readme that calls out the tcl.minor, so we don't see changes there.

[lindsayplatt]

Doesn't it appear that the new fig changes are overplotting axes? Or is that just a visual trick?

[jordansread]

Hard to say if overplotting or retina. I didn't change anything related to append vs replace for axis, so not sure why this would overplot if it didn't before this commit.

[jordansread]

I added a change to the readme to force it to use the tcl.minor default @lindsaycarr

[coveralls]

Changes Unknown when pulling 0aef4656d0f1e16e5afc97d61d2ed8cef0e19e13 on jread-usgs:tcl_minor_default into on USGS-R:master.