Throw error if sources contain main.c

Author: aciidgh

Sources/Transmute/Error.swift

@@ -27,5 +27,6 @@ extension Module {
     public enum Error: ErrorType {
         case NoSources(String)
         case MixedSources(String)
+        case CExecutableNotSupportedYet(String) //TODO: Remove this when add Support for C Exectuable
     }
 }

Sources/Transmute/Package+modules.swift

@@ -90,6 +90,10 @@ extension Package {
         if isSwiftModule {
             return SwiftModule(name: name, sources: sources)
         }
+        
+        //FIXME: Support executables for C languages
+        guard !cSources.contains({ $0.hasSuffix("main.c") }) else { throw Module.Error.CExecutableNotSupportedYet(path) }
+        
         return ClangModule(name: name, sources: sources)
     }