Update the client to the 2.6 release.

[paddycarver]

Update our vendored version of gopkg.in/zorkian/go-datadog-api.v2 to use
the version 2.6 release, which has the fix we need for #31.

[paddycarver]

Test output:

make testacc TEST=./datadog
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./datadog -v  -timeout 120m
=== RUN   TestDatadogDowntime_import
--- PASS: TestDatadogDowntime_import (4.92s)
=== RUN   TestDatadogMonitor_import
--- PASS: TestDatadogMonitor_import (2.97s)
=== RUN   TestDatadogUser_import
--- PASS: TestDatadogUser_import (5.12s)
=== RUN   TestProvider
--- PASS: TestProvider (0.00s)
=== RUN   TestProvider_impl
--- PASS: TestProvider_impl (0.00s)
=== RUN   TestAccDatadogDowntime_Basic
--- PASS: TestAccDatadogDowntime_Basic (2.51s)
=== RUN   TestAccDatadogDowntime_BasicMultiScope
--- PASS: TestAccDatadogDowntime_BasicMultiScope (3.02s)
=== RUN   TestAccDatadogDowntime_BasicNoRecurrence
--- PASS: TestAccDatadogDowntime_BasicNoRecurrence (2.98s)
=== RUN   TestAccDatadogDowntime_BasicUntilDateRecurrence
--- PASS: TestAccDatadogDowntime_BasicUntilDateRecurrence (2.73s)
=== RUN   TestAccDatadogDowntime_BasicUntilOccurrencesRecurrence
--- PASS: TestAccDatadogDowntime_BasicUntilOccurrencesRecurrence (2.76s)
=== RUN   TestAccDatadogDowntime_WeekDayRecurring
--- PASS: TestAccDatadogDowntime_WeekDayRecurring (2.71s)
=== RUN   TestAccDatadogDowntime_Updated
--- PASS: TestAccDatadogDowntime_Updated (4.53s)
=== RUN   TestAccDatadogDowntime_TrimWhitespace
--- PASS: TestAccDatadogDowntime_TrimWhitespace (2.79s)
=== RUN   TestResourceDatadogDowntimeRecurrenceTypeValidation
--- PASS: TestResourceDatadogDowntimeRecurrenceTypeValidation (0.00s)
=== RUN   TestResourceDatadogDowntimeRecurrenceWeekDaysValidation
--- PASS: TestResourceDatadogDowntimeRecurrenceWeekDaysValidation (0.00s)
=== RUN   TestAccDatadogMetricMetadata_Basic
--- PASS: TestAccDatadogMetricMetadata_Basic (4.38s)
=== RUN   TestAccDatadogMetricMetadata_Updated
--- PASS: TestAccDatadogMetricMetadata_Updated (6.82s)
=== RUN   TestAccDatadogMonitor_Basic
--- PASS: TestAccDatadogMonitor_Basic (2.59s)
=== RUN   TestAccDatadogMonitor_BasicNoTreshold
--- PASS: TestAccDatadogMonitor_BasicNoTreshold (2.58s)
=== RUN   TestAccDatadogMonitor_Updated
--- PASS: TestAccDatadogMonitor_Updated (5.24s)
=== RUN   TestAccDatadogMonitor_TrimWhitespace
--- PASS: TestAccDatadogMonitor_TrimWhitespace (2.62s)
=== RUN   TestAccDatadogMonitor_Basic_float_int
--- PASS: TestAccDatadogMonitor_Basic_float_int (4.44s)
=== RUN   TestAccDatadogTimeboard_update
--- PASS: TestAccDatadogTimeboard_update (9.52s)
=== RUN   TestValidateAggregatorMethod
--- PASS: TestValidateAggregatorMethod (0.00s)
=== RUN   TestAccDatadogUser_Updated
--- PASS: TestAccDatadogUser_Updated (5.50s)
PASS
ok      github.com/terraform-providers/terraform-provider-datadog/datadog       80.742s

[bflad]

LGTM

[tombuildsstuff]

LGTM 👍

[catsby]

Confirmed fixes #31 , thanks!

[catsby]

v1.0.1 version is out: https://releases.hashicorp.com/terraform-provider-datadog/1.0.1/

Running terraform init should pull down the new version, unless you have it pinned