- Added support for setting the terminal foreground color.

- Some improvements to error handling.

src/test/groovy/net/rubygrapefruit/platform/PosixFileTest.groovy

@@ -36,7 +36,7 @@ class PosixFileTest extends Specification {
 
         then:
         NativeException e = thrown()
-        e.message == "Could not set UNIX mode on $file. Errno is 2."
+        e.message == "Could not set UNIX mode on $file: could not chmod file (errno 2)"
     }
 
     def "throws exception on failure to get mode"() {
@@ -47,6 +47,6 @@ class PosixFileTest extends Specification {
 
         then:
         NativeException e = thrown()
-        e.message == "Could not get UNIX mode on $file. Errno is 2."
+        e.message == "Could not get UNIX mode on $file: could not stat file (errno 2)"
     }
 }

src/test/groovy/net/rubygrapefruit/platform/TerminalTest.groovy

@@ -20,6 +20,6 @@ class TerminalTest extends Specification {
 
         then:
         NativeException e = thrown()
-        e.message.startsWith('Could not open terminal. Errno is ')
+        e.message == 'Could not open terminal: not a terminal'
     }
 }