Added CeylonScriptTool for compiling and running the ceylon scripts

I've added CeylonScriptTool which will be able to compile and run the ceylon file in a single command.

**Instructions:**
1) Add the line `#! /usr/bin/env ceylon script` at the top of the ceylon file. (Make sure ceylon command is in the PATH)
2) Navigate to project folder.
3) Execute the following commands (Assuming you have following directory structure)
`./source/com/example/myscript/try.ceylon`
OR
`ceylon script source/com/example/myscript/try.ceylon`
OR
`ceylon script` [Not Supported Now, since `ceylon compile` without moduleOrFileName throws error]



**TODO:**
1) Support `ceylon script`
2) Make module search more efficient
3) Detect Version Name from Module