add trim and filter out indentation

[tschallacka]

It would be nice if the text could be trimmed of surplus whitespace and beginning and end and whitespace after \n that corresponds with starting indentation is removed.

so

 /**
  foo
  bar
  */

doesn't turn in

 "
      foo
      bar
      "

but in

  "foo
   bar"

[rimmeraj]

I have a change for this. Once my first pull request is merged I will create a second pull request

[schlebe]

This is interesting but this must be implemented using a parameter in @Multiline !
Example: @Multiline(trim="true")

Sorry, in reading your code, I see that this is already the case.

You have made a good job !

[KnIfER]

I added simple trim and gcc compile support~

see https://github.com/KnIfER/Metaline