Use search api for maven property.

[kounoike]

Current implementation (using maven-metadata.xml) can't lookup some sbt-plugins such as sbt-gitbucket-plugin. So I tried to solve this problem.

I found REST API in API doc. This API can solve this problem.

[xuwei-k]

Please fix tests

• https://github.com/foundweekends/giter8/blob/df63ff633c4025df72bc873d454a876fb1d4b395/library/src/test/scala/giter8/MavenTest.scala
• https://travis-ci.org/foundweekends/giter8/jobs/424005436#L1629

[info] MavenTest:
[info] Maven
[info] - should resolve the latest version when found *** FAILED ***
[info]   The Either on which right.value was invoked was not defined as a Right. (MavenTest.scala:36)
[info] - should return an error when the latest version is not found
[info] - should resolve the latest stable version when the latest version is not stable *** FAILED ***
[info]   The Either on which right.value was invoked was not defined as a Right. (MavenTest.scala:73)
[info] - should return the latest version if the latest version is stable *** FAILED ***
[info]   The Either on which right.value was invoked was not defined as a Right. (MavenTest.scala:95)
[info] - should return an error if the latest stable version is not found

[info] *** 3 TESTS FAILED ***
[error] Failed: Total 55, Failed 3, Errors 0, Passed 52, Ignored 1
[error] Failed tests:
[error] 	giter8.MavenTest
[error] (lib / Test / test) sbt.TestsFailedException: Tests unsuccessful

[kounoike]

@xuwei-k OK I fixed tests and my mistakes.

_

[eed3si9n]

Thanks for the contribution. It looks mostly ok except for the use of http.