Merge pull request #22 from Xeralux/master

Minor fix to allow running jar with "scala scalabuf.jar"
Big project refactoring.

Moved main compiler to scalabuff-compiler subproject.
Merged with the GitHub pull request.
Fixed SBT project file names.
Removed Scala-specific options

Protoc would not compile the files with Scala-specific options.
Fixed ScalaBuffTest.
Fixed ParserTest.
Removed sources in old locations.
Fixes #20: field names are now surrounded by backticks.

All generated public case class field names are now surrounded by
backticks, in order to prevent clashes with reserved
identifiers.

Updated tests to reflect this.
Fixes #21: default values are now recognized

Default options for optional values are now correctly recognized.

Removed getters for optional values, since it's not idiomatic Scala.
Made sure ParserTest output files are closed after each test.
Fixes #23; Improved import statement parsing; added tests

The import statement now correctly supports quotes (support for which
was mistakenly removed in a recent commit).

Added a "import" test to make sure this doesn't happen again.

Improved the Simple test with some more fields with default values.
Fixes #25, invalid generated default enum values

Fields with an enum type which have a default value set had incorrectly
generated default values.

Moved some methods over from Enums to Generator, since they represent a
separate pass over the parse tree.

Made a minor improvement to increase compatibility with ScalaTest 2.10.
Fixes #24: incorrectly generated nested message field types.

Added a relevant test.
Fixes #26, generating nested message field types

Field types of messages that are top level (or generally outside of the
current message) should now be correctly generated.

Updated NestedMessages test.

Updated Empty test.

Started work on message extensions. Generated messages don't compile
correctly yet.
Updated Empty test.
Fixes #29, artifact names now have scalabuff- prepended.
Updated license year.
Updated SBT build, Scala 2.10 is now the default.
Added preliminary "support" for extendable messages. Minor code improvements.