[MacPorts] #17559: Upgrade asymptote port to version 1.56

[MacPorts]

#17559: Upgrade asymptote port to version 1.56
------------------------------+---------------------------------------------
 Reporter:  loshea@…          |       Owner:  macports-tickets@…                   
     Type:  enhancement       |      Status:  new                                  
 Priority:  Normal            |   Milestone:  Port Updates                         
Component:  ports             |     Version:  1.6.0                                
 Keywords:                    |        Port:  asymptote                            
------------------------------+---------------------------------------------
 The attached diff upgrades the Portfile.  Note:
  - The port depends on Hans Boehm's garbage collector library.  Previously
 it satisfied this by downloading a tarball with the lib.  Now it has a
 proper port dependency.  However it needs v7.1 of boehmgc while currently
 that port is at 7.0.  See ticket #17546.
  - Previously the port needed to patch the code slightly.  I believe this
 is no longer necessary, so the patch should be removed.

-- 
Ticket URL: <http://trac.macports.org/ticket/17559>
MacPorts <http://www.macports.org/>
Ports system for Mac OS