Dictionary strong key names

I suggest to add this form to the dictionary initializer:
```
Dim Cities As New Dictionary(Of String, Integer)
From {NewYork = 10, London = 5, Cairo = 12}
```
Note that:
1- I Suggest also to add an implicit line continuation arround the From keyword.
2- No quotations around key names, not only for simplicity, but also to force us to choose valid names to be used as members (see 3).
3- The complier can use this syntax to define strong key names seen only in the dictionary scope so they don't affect other variable names. These keys can be used as follows:
```
Msgbox(Cities.Cairo)
Cities.London = 3
```
Or by the traditional ways:
```
Msgbox(Cities!Cairo)
Cities(London) = 3
```
This will prevent key names mistyping bugs, and give us intillisense autocompletion.

To do this, the compiler can generate a new class that inherits the Dictionary class, and add properties to it with the key names from the initializer!