(Minor) LoaderTest

Modified the content of source(byte[]).
(Minor)(Refactoring) Removal of unused imports

Removed unused imports in CallStackTest & ClassData.
(Refactoring) Replacement of method

Replaced DataType.values()[a.type] with a.getType().
(Refactoring) Eliminating TYPE_MASK from VarEntry
(Minor)(Refactoring)Change of Exception/Error type

RuntimeException -> InternalError, because the error will never be thrown
if this class is correctly implemented.
Addtion of some tests in VarEntryTest

testEquals() fails.
VarEntry#equals()
Attribute "final" on VarEntry
koba/BitUtil (library)
IO / Bugfix of CPU

(1)IO
(2)IOTest
(3)Fixed bug in CALLst instruction.
Modification of IOTest#testCall() / Addition of IOTest to AllTests
Fix in CPUTest / Addition in IOTest / Bugfix in IO

Added test code for IO.putchar(int fd,int ch);
Added if(isStd) in IO.Str#flush()