Add native uuid module.

uuid module provides v4() function which returns a type 4 (pseudo randomly
generated) UUID in string.
Make ScriptableDocument support JSON.stringify.
Fix style errors.

This patch fixes below style errrors.

error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/database/ScriptableQuery.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=16 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableUUID.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=11 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=30 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=35 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=42 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=49 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=79 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=94 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=105 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=128 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=140 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableFuture.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=155 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableConsole.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=11 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableConsole.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=15 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableConsole.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=19 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableConsole.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=23 column=6
error file=/home/sloan/workspace/beyond/core/app/beyond/engine/javascript/lib/ScriptableConsole.scala message=Method name does not match the regular expression '^[a-z][A-Za-z0-9]*$' line=27 column=6