Tag Plots.jl v0.18.0

[attobot]

Repository: JuliaPlots/Plots.jl
Release: v0.18.0
Travis:
Diff: vs v0.17.4
requires vs v0.17.4:

--- 0.17.4/requires
+++ 0.18.0/requires
@@ -1,4 +1,4 @@
-julia 0.6
+julia 0.7-alpha
 
 RecipesBase 0.2.3
 PlotUtils 0.4.1

cc: @mkborregaard

Please make sure that:

• CI passes for supported Julia versions (if applicable).
• Version bounds reflect minimum requirements.

[mkborregaard]

Note that tests fail - this is because Plots' test framework requires the Images.jl stack, which currently has parts that are failing on 0.7. But - the issue is only in the testing dependencies, and Plots works on 0.7.

We've chosen to push a release so that users can have Plots working on 0.7 from the start.