Clarify some points in MAINTAINING.md, add links

MAINTAINING.md

@@ -10,9 +10,9 @@ Repository:
 
 - Update RELEASENOTES file with relevant changes, attributed by contributor (if external). Set date.
 - Update CONTRIBUTORS file (via `git shortlog -sn`)
-- Create and publish a new annotated git tag for the release.
-- Consider to resync the subtree in the native provider repository
-- Consider to update all the repository mirrors (codeplex, gitorious, google)
+- Create and publish a new annotated git tag for the release, e.g. `git tag -a v2.5.0 -m "v2.5.0"`
+- Consider to resync the subtree in the native provider repository.
+- Consider to update the repository mirrors at codeplex, gitorious and google ([how to](http://christoph.ruegg.name/blog/2013/1/26/git-howto-mirror-a-github-repository-without-pull-refs.html)).
 
 Publish:
 
@@ -23,9 +23,9 @@ Publish:
 
 Misc:
 
-- Consider a tweet via @MathDotNet
-- Consider a post to the Google+ site
+- Consider a tweet via [@MathDotNet](https://twitter.com/MathDotNet)
+- Consider a post to the [Google+ site](https://plus.google.com/112484567926928665204)
 - Update Wikipedia release version+date for the [Math.NET Numerics](http://en.wikipedia.org/wiki/Math.NET_Numerics) and [Comparison of numerical analysis software](http://en.wikipedia.org/wiki/Comparison_of_numerical_analysis_software) articles.
-- Regenerate api reference (at numerics.mathdotnet.com/api) using [docu](https://github.com/cdrnet/docu) and deploy to website.
+- Regenerate api reference (at numerics.mathdotnet.com/api) using [docu](https://github.com/cdrnet/docu) and deploy to [website](http://numerics.mathdotnet.com/api/).
 - Update documentation if necessary
 - Consider blog post about changes