updated build script xmldoc patch to save in the same xml file

Implemented fake task that patches xml docs to support <inheritdoc /> for interface implementations, removed snadcastle which is way tooo slow to be useful :(

fixed failing unit test post-refactor

fixed failing builds due to internalvisibleto being removed

nest & elasticsearch.net sign from the csproj file now, remove need for internalsvisibleto, fixed broken yaml test generator
Generate a random key to be able to build if one does not exist build script's release routing will warn if assembly tokens do not match the known Nest/Elasticsearch-Net public key token though.
Build now patches assemblies and nuspec files
now builds docs on release as well and opens a help page after installing the package in visual studio. Appearantly its web control still runs IE8 mode :( add html5shiv to make the docs somewhat readable on IE8

added init powershell scripts that open a breaking-changes page, will most likely be removed later
no longer including public.snk, serves no purpose and msbuild/visual studio will generate keypair.snk/public.snk automatically anyway
Merge pull request #561 from elasticsearch/feature/assembly-signing

Feature/assembly signing