increment ABI versions

SConstruct

@@ -871,7 +871,7 @@ if not preconfigured:
         # fetch the mapnik version header in order to set the
         # ABI version used to build libmapnik.so on linux in src/SConscript
         abi = conf.GetMapnikLibVersion()
-        abi_fallback = [0,6,1]
+        abi_fallback = [0,8,0]
         if not abi:
             color_print(1,'Problem encountered parsing mapnik version, falling back to %s' % abi_fallback)
             env['ABI_VERSION'] = abi_fallback

src/SConscript

@@ -64,7 +64,7 @@ if env['PLATFORM'] == 'Darwin':
     else:
         lib_path = 'libmapnik.dylib'
     linkflags = '-Wl,-install_name,%s' % lib_path
-    linkflags += ' -current_version 0.6.1 -compatibility_version 0.6.1'
+    linkflags += ' -current_version 0.8.0 -compatibility_version 0.8.0'
 elif env['PLATFORM'] == 'SunOS' and env['CXX'].startswith('CC'):
     linkflags = '-R. -h libmapnik.so'
 else: # Linux and others