Use memoist gem instead of carrying a patch in our rails fork.

We upstreamed our patch to memoist here:
https://github.com/matthewrudy/memoist/pull/2

It has been available in memoist since:
v0.11.0 v0.10.0 v0.9.3 v0.9.2 0.9.0 0.2.0

We can now drop our rails fork patch:
https://github.com/ManageIQ/rails/commit/76ba73412f6de3abe775464bba6a8ec9434fdc98

Fixes #538
Added gettext calls into ems_cloud view
Added gettext calls into flavor view
Added missing route "dynamic_list_refresh" to various controllers

https://bugzilla.redhat.com/show_bug.cgi?id=1160890
Merge pull request #982 from skateman/gettext-ems_cloud

Added gettext calls into ems_cloud view
Don't disable GC, let's fix any bugs that caused us to disable the GC.

Fixes #598
Turn off verify_ssl for Ovirt connections
Merge pull request #1021 from brandondunne/set_verify_ssl_false_for_ovirt_connections

Turn off verify_ssl for Ovirt connections
Merge pull request #985 from jrafanie/use_memoist_over_rails_fork_patch

Use memoist gem instead of carrying a patch in our rails fork.
Merge pull request #1009 from AparnaKarve/bz1160890_add_missing_route

Added missing route "dynamic_list_refresh" to various controllers
Merge pull request #998 from skateman/gettext-flavor

Added gettext calls into flavor view
Merge pull request #1020 from jrafanie/dont_disable_gc

Don't disable GC, let's fix any bugs that caused us to disable the GC.