Modify ICU4C and ICU4J test readers to handle all tests
Add `ignoreJava` and `ignoreCpp` properties to tests where needed
Includes parser bug fixes:
ICU4J: require a complex-body after declarations
ICU4J: Correctly parse the complex body after an unsupported statement
ICU4J: Handle date params in tests and remove default params for tests
ICU4J: Handle decimal params in tests
ICU4J: Require whitespace before variable/literal in reserved annotation
ICU4J: Require whitespace between options
ICU4J: Require a variable-expression in an .input declaration
ICU4J: don't require space between last key and pattern in variant
ICU4J: don't require space between selectors
ICU4J: allow whitespace after '=' in option
ICU4J: parse escape sequences in quoted literals according to grammar
ICU4J: allow whitespace within markup after attributes list
