Improve large tables processing. Add tests.

Process large tables on different areas the same way as usual tables.
Process large tables with custom width.
Prohibit adding new content to completed large table.
Remove last flushed row group from completed table. Fix a test.

DEVSIX-1646

Autoported commit.
Original commit hash: [1527d6352]

Author: ars18wrw

itext.tests/itext.layout.tests/itext/layout/LargeElementTest.cs

@@ -66,6 +66,8 @@ public class PdfException : Exception {
 
         public const String BadUserPassword = "Bad user password. Password is not provided or wrong password provided. Correct password should be passed to PdfReader constructor with properties. See ReaderProperties#setPassword() method.";
 
+        public const String CannotAddCellToCompletedLargeTable = "The large table was completed. It's prohibited to use it anymore. Created different Table instance instead.";
+
         public const String CannotAddKidToTheFlushedElement = "Cannot add kid to the flushed element.";
 
         public const String CannotAddNonDictionaryExtGStateToResources1 = "Cannot add graphic state to resources. The PdfObject type is {0}, but should be PdfDictionary.";