Add CLI, sbt-assembly and very basic compiler skeleton

Example of CLI:

    java -jar mjc.jar --verbose --debug --stop-after-phase:"typer" Hello.java
    Error: File /home/soc/Entwicklung/mjis/target/scala-2.11/Hello.java does not exist!

    mjc 0.1
    Usage: java -jar mjc.jar [options] <file>...

      --stop-after-phase <value>
            Run compiler until specified phase
      --verbose
            Print information about what the compiler is doing
      --debug
            Print debug information
      <file>...
            Input files (*.java or *.mj)

Example sbt-assembly:

    > assembly //creates stand-alone mjc.jar
Merge pull request #9 from soc/topic/compiler-cli

Add CLI, sbt-assembly and very basic compiler skeleton
Add AnalysisResult and Finding classes.

The AnalysisResult class is intended to hold the results of the analysis
phases (lexical, syntactic and semantic analysis).

In order to allow for a "pull parser" model where the parser starts
before the lexer has finished, the results and the findings list are
implemented as Streams.

There is a lazy val success that invokes a callback. This callback
should advance the analysis to a point where the success of the phase
can be determined.

The findings are supposed to be subclasses of the abstract Finding
class. They can take parameters and can output a description of the
finding.
Merge pull request #10 from jspam/006-analysis-result

Add AnalysisResult and Finding classes.
Add basic lexer tests.

Test whitespace, operators/keywords, identifiers, integer literals
and some failure cases.

The tests are ignored for now because they would still fail. To make the
tests run, replace "ignore" by "it" in front of the tests.
Remove token class for "import" keyword.

It does not occur in the MiniJava grammar according to the language specification.
Merge pull request #12 from jspam/007-import-unused

Remove token class for "import" keyword.
Merge pull request #11 from jspam/005-lexer-tests

Add basic lexer tests.
Add Lexer test for separating tokens without whitespace.

Tokens do not need to be separated by whitespace, e.g. a[b] is 4 tokens.
Add a test for that (ignored for now because the lexer is not yet implemented.)
Remove options from CLI, add lextest
Merge pull request #20 from soc/topic/cleanup-cli

Remove options from CLI, add lextest
Remove *.mj/*.java file name requirement

It is not mentioned in the spec and could lead to problems with
automated tests by the course instructors (their test files might be
named differently).
CLI: Make --lextest not take a string, add help string

opt[String] would imply a parameter of the form "--lextest <value>", but
the specification on the assignment sheet says --lextest does not take
any values but the file name (which is a separate parameter).
Merge pull request #24 from jspam/011-lextest-parameter

CLI: Make --lextest not take a string, add help string
Merge pull request #23 from jspam/010-file-extensions

Remove *.mj/*.java file name requirement
Convert case classes to case objects
Merge pull request #21 from soc/topic/case-objects

Convert case classes to case objects
Merge pull request #17 from jspam/008-moar-lexer-tests

Add Lexer test for separating tokens without whitespace.
Integrate AnalysisResult directly into the Phase classes.

All phases return some result. This is useful for unit testing and
dumping a result. There is a subtrait AnalysisPhase which additionally
has a success value. This is for lexical, syntactic and semantic analysis.
The rest of the phases should not be able to fail.
Merge pull request #25 from jspam/014-integrate-analysis-result

Integrate AnalysisResult directly into the Phase classes.