Use the same comment preflight for tasks

Realized that there's no reason to use 4 different files
when 1 file can do the whole thing.  So consolidated the
two 2 task comment preflights into a single
preflight 'prepareCommentReplyEmail'.  Plus it has a
dramatically shorter, and more awesome, file name.

Updated settings file to specify which template to use.

Updated the preflight to check whether the target is a
task or a project, and perform the appropriate model
lookups.
Consolidate comment templates

Both task and project emails use the same basic format.
Instead of having separate email templates for both,
just use one template and check in the template whether
the email is about a task or project.

Update wording in the subject lines to be a bit more
friendly and logical.