Include xml doc in package

Fixes #6
Add strong name to assembly & sign.

Sign test as well, will break build if main project isn't signed properly, this effectively adds a test-case
for the signing of the main project.

Fixes #5
Documentation improvements - ExampleUsage project etc
Bugfix - check if table exists before creating
More code-doc
Bump to v1.1.0

Add ef-enum-to-lookup.nuspec to sln for convenience.

Minor as interface changed (added missing properties) as per semver.org.