Adds format lifecycle and Java formatting.

[ctrimble]

This adds a format lifecycle to maven and binds the eclipse formatter to it.

Usage:

mvn format

[ochafik]

This is great, thanks a lot!

I've found a small number of issues in the resulting format, might need some minor tweaking (of the code or of the settings :-)) in a further commit:

• multiline comments are transformed to single-line, which is an issue for some rare comments containing improperly escaped code snippets (join_lines_in_comments is currently true)
• a couple of enums are put in a single line, which I find less readable
• need to transform some triple-slash single line comments to double slash (otherwise get transformed to // /)
• some tests seem less readable, is there a way to mark files to be skipped with a special comment, maybe? (for instance, DemanglingTest.java)

[ctrimble]

@ochafik There is a tag based on/off feature in the formatter, but I have not played with it yet. I will checkout how it works tonight.