Make the parser compatible with EBCDIC plaforms like z/OS

[michaelknigge]

The Greenfield parser assumes that it runs on ASCII platforms and for this reason does not provide information about the charset that is to be used for byte[] to String (and vice versa) conversations. Java then uses the charset that is specified by the system property file.encoding.

On z/OS (i.e.) file.encoding might be IBM-500 (EBCDIC-International) and then the parser converts a read byte[] to a String using this charset...

[codecov]

Codecov Report

Merging #377 into integration will increase coverage by 0.03%.
The diff coverage is 12.12%.

@@                Coverage Diff                @@
##             integration     #377      +/-   ##
=================================================
+ Coverage           25.2%   25.23%   +0.03%     
  Complexity           877      877              
=================================================
  Files                232      231       -1     
  Lines              12816    12800      -16     
  Branches            1829     1829              
=================================================
  Hits                3230     3230              
+ Misses              9208     9192      -16     
  Partials             378      378

Impacted Files	Coverage Δ	Complexity Δ
...ava/org/verapdf/pd/font/cff/CFFFileBaseParser.java	75% <ø> (ø)	23 <0> (ø)	⬇️
src/main/java/org/verapdf/cos/visitor/Writer.java	0% <0%> (ø)	0 <0> (ø)	⬇️
...va/org/verapdf/tools/EncryptionToolsRevision4.java	0% <0%> (ø)	0 <0> (ø)	⬇️
src/main/java/org/verapdf/cos/COSStream.java	22.15% <0%> (ø)	7 <0> (ø)	⬇️
src/main/java/org/verapdf/pd/colors/PDIndexed.java	0% <0%> (ø)	0 <0> (ø)	⬇️
...in/java/org/verapdf/pd/font/type1/PDType1Font.java	0% <0%> (ø)	0 <0> (ø)	⬇️
.../main/java/org/verapdf/parser/SignatureParser.java	0% <0%> (ø)	0 <0> (ø)	⬇️
src/main/java/org/verapdf/cos/COSString.java	13.79% <0%> (+0.45%)	8 <0> (ø)	⬇️
...main/java/org/verapdf/pd/font/cmap/CMapParser.java	48.36% <0%> (ø)	28 <0> (ø)	⬇️
...va/org/verapdf/pd/font/type1/Type1FontProgram.java	0% <0%> (ø)	0 <0> (ø)	⬇️
... and 7 more

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[BezrukovM]

The main changes looks ok, but it looks like the org.verapdf.cos.visitor.Writer class has been affected by some sort of auto formatting. The result has not the same code style as all other classes in veraPDF. So, can you, please, update the branch and remove code style changes for that class. Thank you.

[michaelknigge]

I've reverted back to the original coding conventions. Please review again, Thank you.

[BezrukovM]

@michaelknigge Thanks a lot for your PR. All changes will be added in our code soon, but I will close this PR and the reasons will be described in veraPDF/veraPDF-library#1032