Allow user to add option when using the LessFilter
LessFilter: Add setLoadPaths method
ScssFilter: Add setLoadPaths method
LessphpFilterTest can't inherit LessFilterTest because we didn't use the same options
Allow user to add Parser option such as "relativeUrls"
We can't use parserOptions attributes because each assets alter this var
add a setWrap method to the UglifyJs2 filter.
Merge pull request #417 from igwan/patch-1

add a setWrap method to the UglifyJs2 filter.
Merge pull request #404 from ksamc/master

Add setLoadPath method to LessFilter and Sass/Scss-Filter
Merge pull request #403 from BenoitLeveque/add-option-less-filter

Allow user to add option when using the LessFilter
added "http" test group
child inherits env by default
Merge branch 'master' of https://github.com/kriswallsmith/assetic into set-options