Code refactoring in Java execution strategy.
Update README.md
Update README.md
Implemented PHP CGI execution strategy.
Allowed HTML in test input/output.
Added the Java Sandbox Executor code into the code and removed the requirement for file.
Fixed StyleCop violation of spacing in TestsController in the administration.
Refactored the Java execution strategy not to use Java archiver. Closes #3
Implemented async reading of compiler process output and error streams.
Implemented PHP CLI execution strategy. Closes #4.
Added Java, PHP CGI and PHP CLI submission types in the seed method for submission types.
Merge pull request #477 from vladislav-karamfilov/master

PHP execution strategy implemented and other improvements