Renamed `resources` in allocator to `toAllocate`.
Renamed `resources` in allocator to `toAllocate`.

`resources` is currently used in the allocator to denote
resources that are going to be allocated. This name is too
general and ambiguous. Renamed it to `toAllocate` for
better readability.

Review: https://reviews.apache.org/r/66045/

reneploetz/mesos,gsantovena/mesos,Gilbert88/mesos,gsantovena/mesos,kaysoky/mesos,jpeach/mesos,asamerh4/mesos,Gilbert88/mesos,gsantovena/mesos,gsantovena/mesos,jpeach/mesos,chhsia0/mesos,chhsia0/mesos,chhsia0/mesos,Gilbert88/mesos,gsantovena/mesos,chhsia0/mesos,kaysoky/mesos,andschwa/mesos,dforsyth/mesos,chhsia0/mesos,andschwa/mesos,Gilbert88/mesos,kaysoky/mesos,kaysoky/mesos,abudnik/mesos,asamerh4/mesos,reneploetz/mesos,jpeach/mesos,asamerh4/mesos,Gilbert88/mesos,jpeach/mesos,abudnik/mesos,andschwa/mesos,dforsyth/mesos,jpeach/mesos,abudnik/mesos,dforsyth/mesos,asamerh4/mesos,gsantovena/mesos,andschwa/mesos,abudnik/mesos,Gilbert88/mesos,andschwa/mesos,dforsyth/mesos,abudnik/mesos,chhsia0/mesos,asamerh4/mesos,jpeach/mesos,andschwa/mesos,reneploetz/mesos,dforsyth/mesos,abudnik/mesos,Gilbert88/mesos,chhsia0/mesos,jpeach/mesos,reneploetz/mesos,abudnik/mesos,dforsyth/mesos,kaysoky/mesos,reneploetz/mesos,kaysoky/mesos,asamerh4/mesos,reneploetz/mesos,gsantovena/mesos,kaysoky/mesos,andschwa/mesos,dforsyth/mesos,reneploetz/mesos,asamerh4/mesos