Constant strings for tokens.

Minor: refactoring, java code conventions
Markers for parsing errors.

 #KT-5540 Fixed
Showing markers for zero-length ranges.
Parsing errors are now shown right after opening eclipse.

Minor: refactoring
Autotesting framework.
Autoimport tests are now automatic.
Error tags refactored, warning tags added.

Minor: refactoring
Caret tag is now the constant string in the KotlinEditorTestCase class.

Minor: refactoring
Break line tag is now the constant string in the KotlinEditorTestCase class.

Minor: refactoring
getCursorPosition method doesn't make any sense.

Minor: refactoring
Autotesting framework changed. SourceFile class found (reused and refactored). WithAfterSourceFileData class added.

Minor: refactoring
Tests for parsing errors' markers added.

Minor: refactoring
Test with typing a character added. typedCharacter method in TypingUtils class gets the character specified in comment.
Refactoring after rebasing onto closing-bracket-fix branch.

Minor: refactoring