* Set up CI with Azure Pipelines
[skip ci]
* Add task for testing without GMP
* Add C++ testing + no GMP on windows
* Add the Nim wrapper for GMP to Azure build
* Add Azure badge
* Fix nimble test tasks
* Workaround windows path in Azure
* Fix nim binaries path and mingw on 32-bit
* add stew test dependency
* Fix nim/nimble path
* disable GMP tests on windows
Mamy Ratsimbazafy