fix issue #5 for support express>=2.5.11
Added header support to csv
Fix function call
Test first object to see if an array or object
add .csv extension to the file download
File Disposition

Only set file name if hasn't already been set previously
Merge branch 'master' of http://github.com/jozzhart/express-csv

Conflicts:
	lib/express-csv.js
Merge branch 'master' of http://github.com/LabiKyo/express-csv

Conflicts:
	lib/express-csv.js
Merge branch 'master' of http://github.com/mattvoss/express-csv

Conflicts:
	lib/express-csv.js
merge fixes
Updates for test because of fail:
 looks that new express not have express.version -variable and causes test fail
Update package.json to support express >2.