The build process should not rely on extremely long paths

[corranrogue9]

The OData.sln, OData.E2E.sln, and OData.Pipeline.sln solutions fail to build if the repo is cloned in a path that is too long. I don't know the limit, but I know that if you clone the repo into a path that is 57 characters (such as c:\aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa), this build failure will reproduce.

1. We should not require such long paths during build in the first place
2. Where we do require long paths, we should only be using build utilities that support those long paths (rather than ones that fail to find the files in those paths and produce build failures)
3. When these two issues are addressed, the onboarding .md files in the sln folder should be update to remove their suggestion to use a very short path as the root of the onboarder's repo