Aruba: changed dependencies management and better error handling and retries

1. changed dependencies management to govendor
2. better error messages (use messages from SL)
3. retry policies when request fails (defaults to 1)

Thanks for @mattcui @zhanggbj and @bondyk for contributions

Curacao: adding create[Public]ArchiveTransaction and making http/https scheme settable

1. added support for VGBDTG#createPublicArchiveTransaction
2. added support for VG#createPublicTransaction
3. allow customization of the HttpClient class so that the http/https scheme can be settable

U.S. Virgin Islands: dealing with HTTP errors and new `develop` branch

Major changes in this U.S. Virgin Islands release are:

1. we now deal with HTTP errors 40x and 50x (issue #93)
   a. lots of changes and tests but should be backward compatible
   b. we report these HTTP errors as Golang error (even in cases where SL API does not)
2. started using develop branch in develop/master process
3. new concourse.ci pipeline for both master and develop. We will make these publicly visible soon
4. various changes to integration tests to streamline and skip DNS integration tests which require an SL account with special priviledges

Cayman Islands: TheWeatherCompany updates plus some changes to VGBDTG

1. added addLocations, removeLocations, setAvailableLocations to VGBDTG
2. Changed .travis.yml to use Go 1.4.2 and new location for Golang crypto libraries
3. Small changes due to lack of formatting using go fmt
4. TheWeatherCompany PR adding support for:
   • SoftLayer_Dns_Domain_Service
   • SoftLayer_Dns_Domain_ResourceRecord_Service
   • VirtualGuest_Service#UpgradeObject
   • VirtualGuest_Service#GetAvailableUpgradeItemPrices

British Virgin Islands: stable release for bosh-softlayer-cpi

This is a stable release that includes various updates to get the BOSH SoftLayer CPI code to work and deploy the latest CF release via it's pipeline. Various additions too numerous to list here.

I will be more vigilant about tagging and creating releases matching new major updates.

St. Lucia: passing Travis build

Various improvements, especially implementing methods around user metadata, e.g., setUserMetadata and configureMetadataDisk.

Also, added Travis support and passing build running unit tests.