Fixes #142 - Deploy the automatic build on Appveyor (#144)

* First configuration stub

* Get rid of the old winsw_cert.pfx references, adjust docs

* Fix the corrupted log4net reference, we use 2.0.3

* Generate stub SNK file

* Signing: Try full SDK path to generate SNKs

* Fix the path

* Signing: Sign all assemblies being packed into WinSW

* Tests: Try enabling tests

* Tests and artifacts: Use absolute paths

* Artifact path must be relative

* The test DLL is the NUnit one

* nunit-console does not require loggers

* NUnit: Try picking all DLLs in the output folder

* NUnit console: No wildcards

* Tests: Fix the test project to make it properly working with the new project structure

* Docs: Clarify the specifics of external extension usage

* Add AppVeyor badge to README.md

doc/extensions/extensions.md

@@ -28,5 +28,7 @@ Generic extension creation guideline:
 
 WinSW engine will automatically locate your extension using the class name in the [XML Configuration File](../xmlConfigFile.md).
 See configuration samples provided for the extensions in the core.
+For extensions from external DLLs, the `className` field should also specify the assembly name. 
+It can be done via fully qualified class name or just by the `${CLASS_NAME}, ${ASSEMBLY_NAME}` declaration.
 
 Please note that in the current versions of WinSW `2.x` the binary compatibility of extension APIs *is not guaranteed*.