Replace `setblockcolour()` argument with `const char*`

There's no reason it needs to be an std::string here.

Although, realistically, we should be using an enum instead of
string-typing, but, eh, that can be fixed later.

desktop_version/src/BlockV.cpp

@@ -1,5 +1,7 @@
 #include "BlockV.h"
 
+#include <SDL_stdinc.h>
+
 blockclass::blockclass(void)
 {
     clear();
@@ -37,57 +39,57 @@ void blockclass::rectset(const int xi, const int yi, const int wi, const int hi)
     rect.h = hi;
 }
 
-void blockclass::setblockcolour( std::string col )
+void blockclass::setblockcolour(const char* col)
 {
-    if (col == "cyan")
+    if (SDL_strcmp(col, "cyan") == 0)
     {
         r = 164;
         g = 164;
         b = 255;
     }
-    else if (col == "red")
+    else if (SDL_strcmp(col, "red") == 0)
     {
         r = 255;
         g = 60;
         b = 60;
     }
-    else if (col == "green")
+    else if (SDL_strcmp(col, "green") == 0)
     {
         r = 144;
         g = 255;
         b = 144;
     }
-    else if (col == "yellow")
+    else if (SDL_strcmp(col, "yellow") == 0)
     {
         r = 255;
         g = 255;
         b = 134;
     }
-    else if (col == "blue")
+    else if (SDL_strcmp(col, "blue") == 0)
     {
         r = 95;
         g = 95;
         b = 255;
     }
-    else if (col == "purple")
+    else if (SDL_strcmp(col, "purple") == 0)
     {
         r = 255;
         g = 134;
         b = 255;
     }
-    else if (col == "white")
+    else if (SDL_strcmp(col, "white") == 0)
     {
         r = 244;
         g = 244;
         b = 244;
     }
-    else if (col == "gray")
+    else if (SDL_strcmp(col, "gray") == 0)
     {
         r = 174;
         g = 174;
         b = 174;
     }
-    else if (col == "orange")
+    else if (SDL_strcmp(col, "orange") == 0)
     {
         r = 255;
         g = 130;

desktop_version/src/BlockV.h

@@ -12,7 +12,7 @@ public:
 
     void rectset(const int xi, const int yi, const int wi, const int hi);
 
-    void setblockcolour(std::string col);
+    void setblockcolour(const char* col);
 public:
     //Fundamentals
     SDL_Rect rect;

desktop_version/src/Entity.cpp

@@ -1078,7 +1078,7 @@ void entityclass::createblock( int t, int xp, int yp, int w, int h, int trig /*=
 
     if (customactivitycolour != "")
     {
-        block.setblockcolour(customactivitycolour);
+        block.setblockcolour(customactivitycolour.c_str());
         customactivitycolour = "";
     }