Bump in Edifice: common4

[chapulina]

Bump edifice to use ign-common4 and ign-fuel-tools6.

The script in #333 should be helpful.

#331 may also be a helpful reference.

[scpeters]

for osrf/homebrew-simulation, I think we need an ignition-common4 formula first, and it would be easier if we combined all those pull requests that update dependencies into a single PR, since new bottles need to be built at the same time

[chapulina]

we need an ignition-common4 formula first

Ahh it was there, I just forgot to open the PR: osrf/homebrew-simulation#1308

it would be easier if we combined all those pull requests that update dependencies into a single PR

I originally kept them separate because I remember having trouble with a single PR. But if that's preferred I can combine them like I've been doing for release-tools and gazebodistro.

The tricky part is having all CI green before merging each source code PR, which requires nightlies for dependencies...

[scpeters]

The tricky part is having all CI green before merging each source code PR, which requires nightlies for dependencies...

the alternative is to disable bottles by deleting the bottle block in affected formulae; then you can update formaule incrementally, but this has an effect of making our CI slow as well. we can also do a combination; disable bottles for edifice, launch, and gazebo, then update their dependencies all at once. it just depends on which package is the most problematic