add function symbol and remove function symbol added to DisAsm debugger view 

Right click adds these two options.

Before merging consider that this uses the status bar to output failure conditions `SendMessage(GetParent(wnd), WM_DEB_SETSTATUSBARTEXT, 0, (LPARAM) statusBarTextBuff);`

Also, the math for symbol insertion is done in the view class `int newSize = curAddress - prevAddr;`. Can be moved to an `InsertSymbol` function in the symbolMap but I wrote this before I made the modifications in the symbol map. So if this is wished before the merge, just comment underneath.

I don't particularly enjoy the `char statusBarTextBuff[256];` allocations everywhere, as the magic numbers are questionable but it's used in the surrounding code, so I just used it.

Last point of discussion would be default name "u_un_%08X" for new user placed function symbols.

As always, if this isn't considered useful for the project, feel free to reject.

![image](https://f.cloud.github.com/assets/465677/1438225/f73b13ce-4179-11e3-89f6-5443cbb1cc20.png)