Adds new :evaluated Modifier

[juanpedromoreno]

This PR brings an additional tut:evaluated modifier in order to be able to post just the evaluated statement as output.

println(1 + 1)

will produce:

2

When this new feature might be useful? For instance, together with the sbt-buildinfo plugin we could:

println(s"""libraryDependencies += "your.organization" %% "artifact" % "${yourpackage.BuildInfo.version}"""")

will produce the following output:

libraryDependencies += "your.organization" %% "artifact" % "1.2.3"

in case that 1.2.3 is the current version for the artifact.

Please, review at your convenience. Thanks!

[tpolecat]

Hi, this looks good. Can you add a few more tests please:

• The current test shows that printed output is captured; can you also show that the result of evaluating an expression is shown (i.e., 2+2)?
• It would be helpful to show what happens if you have multiple expressions in an :evaluated block (mostly the newline behavior in between).
• What happens when combined with other modifiers (:book for instance)?

[juanpedromoreno]

Hi, I've just added few more test cases that may cover the points you mentioned. Could you verify it? Please, let me know if something additional could be added. Thanks!

[tpolecat]

Perfect! Great contribution, thank you!