Improves check for api requests.

Timelines introduces a case where the json format is negotiated
but not represented in the format parameter via routes (i.e., the
extension ".json"). This change adds support for Accept-header content
negotiation, which results in the format field of the request. For
consistency, xml was also added.
fixes estimated_hours validation on issues by explicitly making it fail on invalid input strings
some tests for estimated_hours validation
add cuke for renaming wiki pages
updated gems
[OPF #492] fixes special chars in issue subject
[OPF #487] fixes pagination links

- fixed css for 'prev' and 'next' pagination links
Move ajaxapender.js to separate file.
Move issues.js to separate file and implement client-side quoting for issues.
Add HTML classes to simplify jquery matching.
Implement new route and controller action for issue quotes.
Delete 'journals#new' as journals are not created directly and quoting now uses 'issues#quoted'.
Change link to quoted action to new route.
Use before_filter for new 'quoted' action.
Update 'quote' links and add permission for 'quoted' action.
Update .travis.yml

let travis only test 1.9.3
fixed bad usage of html_safe
[OPF #483] fixes timelog report layout

- added html_safe for timelog report and report_criteria
make code for time entries reports more readable
fixed js error on time report