#1111 document optional title= argument in release command

[kreinba]

The #1111 proposal — letting users override the GitHub release title from the
release comment — is already wired in code: CommentsTag.title() reads
args/arg[@name='title'] and falls back to the issue title, the
QnParametrized parser turns title=\...`into that arg, andcreatesReleaseTitleFromTalkinCommentsTagTest` covers the path. Only the
documentation was missing.

The basics post now shows the optional title= argument next to the existing
tag= example, so users can see how to invoke it without reading the source.

This is a documentation-only change to a Jekyll post, no Java, no resources, no
tests touched. Local diff is seven added lines in
src/jekyll/_posts/2014/jul/2014-07-13-basics.md; no build or test command
applies to that file.

Closes #1111