Windows port

I've made a few changes to support installing on Windows.

In addition, ran into couple of bugs:

- replaced used of single quotes with double quotes in Tcl strings; for example

```
set os_path_sep ':'
```
should be 
```
set os_path_sep ":"
```
- TestObj::execute was using a exception object outside its scope in the verdict == FAILURE case.

/Ashok
Actually, I'm thinking to convert the whole project to MIT license and only have an AUTHORS file in the root directory listing project particpants and their contributions. Is that ok with you?