v1.1.2: Added/improved message on assert errors

While assert are not part of the package's interface,
they tend to trigger during development.
Confusing or absent message can confuse developers,
so Bitblob will now show those better error messages on assert error.

When calling this(scope const ubyte[] binary, bool isLittleEnding = false):

ubyte[] argument to BitBlob!256LU constructor does not match the expected size of 32LU

When calling this(scope const(char)[] hexstring):

Length of string passed to BitBlob!256LU constructor does not match the expected size of 32LU