Feature/config via commandline

This feature enables command line config instead of requirement to have .munit and target.hxml files available. Some undocumented command line arguments has been used from original approach `munit run {config} {src} {testbin} {report}` the rest is avaialbe using **config:** or **target:** prefixes. Following .munit:
```
version=munit
src=src/test/haxe
bin=bin/test
report=bin/test-report
hxml=munit.hxml
classPaths=src/main/haxe
coverageIgnoredClasses=module
```
and target.hxml file:
```
#neko
-main TestMain
-lib munit
-cp src/main/haxe
-cp src/test/haxe
-neko bin/test/neko_test.n
```

can be now executed as following command (notice **cliconfig**):
```haxelib run munit test cliconfig src/test/haxe bin/test bin/test-report config:classPath=src/main/haxe config:coverageIgnoredClass=module target:main=TestMain target:lib=munit target:cp=src/main/haxe target:cp=src/test/haxe target:neko=bin/test/neko_test.n```

Updates in code should not affect any previous munit functionality. If suggested changes are not welcomed let me know, I will make a repo fork instead...