Remove trailing spaces
Add SBT installation instructions link
Fix receiver typo
Fix deprecation issues.

The 'val' in the for comprehension is unneeded and deprecated, so I removed it.
'Integer' is deprecated - I've switched to the Scala specific Int, which can
never be null
Merge pull request #5 from bobtfish/master

Fix deprecation warnings..
Merge pull request #3 from vti/master

Small README improvements
Merge pull request #4 from vti/typo

Fix receiver typo
Scala style changes.
Merge remote-tracking branch 'upstream/master'
Merge pull request #6 from gphat/master

Scala-stylify Moe
Remove some strings before method signature.
Methods with only a match should just use match, not wrap it in {}
;s are not needed
Add add wildcard match to Interpreter to catch unknown node types, with
test.
Merge pull request #7 from gphat/master

Minor nits and a warning fix.
Use Option inside MoeObject rather than nulls, as it's more idiomatic
and more useful in the future.
Merge pull request #8 from gphat/master

Use Option in MoeObject