Fog::Model#wait_for: eliminate inner retry loop

AWS frequently takes more than 3 seconds for an instance to appear.
Rather than having the overlapping timeouts for reload and
instance_eval, simply make them both occur with the same timeout.

 + Prevents spurious failures when waiting for AMI
 + Easier to follow flow
[cloudstack] add disk_offerings, os_types mock data
[cloudstack] add list_os_types, list_disk_offerings request mocks
[cloudstack] list_os_types, list_disk_offerings request tests, rm pending
Merge pull request #1750 from dm1try/cloudstack_add_list_os_types_and_list_disk_offerings_mocks

[cloudstack] Add list os types and list disk offerings mocks
Merge pull request #1748 from maginatics/timeout2

Fog::Model#wait_for: eliminate inner retry loop
[cloudstack] servers collection, add attributes to :all method
Merge pull request #1754 from dm1try/cloudstack_add_attributes_to_servers_method

[cloudstack] servers collection, add attributes to :all method
Changes the path only if subdomain is not @host

see https://github.com/fog/fog/issues/1631#issuecomment-16396992
Merge pull request #1757 from mhuin/fix_subdomain_check

Changes the path only if subdomain is not @host
fix case where volume isn't instantly available to attach upon creation
Merge pull request #1758 from AltJ/master

Wait for volume to be available before attaching
Merge branch 'master' of github.com:fog/fog into not_found