dimitri
Try harder to keep update cached recipe
Let the safe properties be updated even if others are not known to be safe. This is a prequisite to solving #2232. See also https://github.com/dimitri/el-get/pull/2238#issuecomment-138383276. Fixes #2359.
Additionally, always use display-warning when properties can't be updated instead of hiding the warning in the *Messages* buffer. This can be suppressed by adding (el-get recipe-cache) to warning-suppress-types, which is the standard Emacs mechanism for supressing warnings, but it's not very discoverable so some users may find the warnings annoying. I added the actions needed to fix the problems into warnings themselves in the form of clickable links/buttons, so hopfully it won't be too bad.
There are errors during self update again, so I'll see if I can add some backwards compat code to smooth it out before merging this.
transition install seems okay, ~~but I just got
el-get-describe-1: Symbol's function definition is void: el-get-insert-button
need to double check that.~~ fixed, was a stupid mistake.
~~el-get-compute-new-status is returning wrong result for the REQUIRED part.~~ Fixed, and tests added.
