[encoding] Creating test suites for each encoding. (#30)

For example:
test-big5.txt
test-big5.utf8.txt
And the test-big5.txt just contains all the valid characters in BIG5 encoding.

test-big5.invalid.txt
test-big5.invalid.utf8.txt
And test-big5.invalid.txt
 contains invalid characters in text along with valid characters
The file test-big5.invalid.utf8.txt would contains the corresponding valid characters.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/encoding/issues/30