Bump to build number 2
Bump to build number 2

Appears the some new `gcc` libraries slipped in during the build of
`matplotlib`. The result is that it got linked to these and became
dependent on them. Looks like the cause is some packages coming from
`defaults`. Namely `python` and `readline`. This is due to the fact that
`python` 2.7 and `python` 3.5 were not dependent on `readline` 7.0 yet.
However that has since been fixed. Hence this should be resolved with a
simple rebuild.

conda-forge/matplotlib-feedstock