Add a few overview bullet points
Clean up the wording in a few places
document String#to_time exception
fix typo
Simple grammar updates
added to rdoc for unscope that default_scope wins
Capitalizing internet to Internet. [ci skip]
replace apostrophe with backquote for matching [ci skip]
Add some documentation for AM.mailer_name
Fix incorrect post_path link generation.
Remove unopened closing brace.
Fix another incorrect post_path link generation.
Update CreateComments migration to reflect the output from Rails 4.
comments in the callbacks description are in present tense
Changing the wordings in a few places
dir -> directory
2.15.1 is the first release that supports Rails 4.

specifically manifest.json
Improve model generator USAGE grammar
Fix grammar on AM.mailer_name documentation.
XML-files isn't a word