Rewrite 'with-curl-easy' macro

[fraya]

Right now only binds a name and creates an object from class <curl-easy>. It should be a variable and be assigned to an expression, like with-open-file macro. This way is possible to subclass <curl-easy> or use a function that initializes a <curl-easy> request.

dylan-curl/src/curl-easy.dylan

Line 552 in 1a8f655

{ with-curl-easy (?curl:name) ?body:body end }