ENH: added OStringStream reset method (closes #534)

- resets the output buffer completely - implementing what rewind was
  likely meant to have accomplished for many use cases.

STYLE: OSHA1stream reset() for symmetry. Deprecate rewind().

applications/test/OStringStream/Test-OStringStream.C

@@ -52,9 +52,11 @@ int main(int argc, char *argv[])
     Info<< "overwrite with short string:" << nl
         << os.str() << endl;
 
-//  os.reset();
-//  Info<< "after reset:" << nl
-//      << os.str() << endl;
+    os.reset();
+    os << "%%%% reset";
+
+    Info<< "after reset:" << nl
+        << os.str() << endl;
 
     Info<< "End\n" << endl;
 

applications/test/error/Test-error.C

@@ -47,8 +47,24 @@ int main(int argc, char *argv[])
 
         IOWarningInFunction(dict) << "warning 3" << endl;
 
-        FatalErrorInFunction << "error 1" << endl;
-        FatalErrorInFunction << "error 2" << exit(FatalError);
+        FatalErrorInFunction
+            << "This is an error from 1" << nl
+            << "Explanation to follow:" << endl;
+
+        FatalErrorInFunction
+            << "Error 2"
+            << exit(FatalError);
+    }
+    catch (Foam::error& fErr)
+    {
+        Serr<< "Caught Foam error " << fErr << nl << endl;
+    }
+
+    try
+    {
+        FatalErrorInFunction
+            << "Error# 3"
+            << exit(FatalError);
     }
     catch (Foam::error& fErr)
     {

applications/test/sha1/Test-SHA1.C

@@ -96,7 +96,7 @@ int main(int argc, char * argv[])
         os  << str;
         Info<< os.digest() << endl;
 
-        os.rewind();
+        os.reset();
         os  << "The quick brown fox jumps over the lazy dog";
         Info<< os.digest() << endl;
     }