Task description

• Implement a ParsePositiveFromOctal extention method that сonverts the string representation of a positive number in the octal numeral system to its 32-bit signed integer equivalent.
• Implement a ParsePositiveFromDecimal extention method that сonverts the string representation of a positive number in the decimal numeral system to its 32-bit signed integer equivalent.
• Implement a ParsePositiveFromHex extention method that сonverts the string representation of a positive number in the hex numeral system to its 32-bit signed integer equivalent.
• Implement a ParsePositiveByRadix extention method that сonverts the string representation of a positive number in the octal, decimal or hex numeral system to its 32-bit signed integer equivalent.
• Implement a ParseByRadix extention method that onverts the string representation of a signed number in the octal, decimal or hex numeral system to its 32-bit signed integer equivalent.
• Implement a TryParsePositiveFromOctal extention method that сonverts the string representation of a positive number in the octal numeral system to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
• Implement a TryParsePositiveFromDecimal extention method that сonverts the string representation of a positive number in the decimal numeral system to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
• Implement a TryParsePositiveFromHex extention method that сonverts the string representation of a positive number in the hex numeral system to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
• Implement a TryParsePositiveByRadix extention method that сonverts the string representation of a positive number in the octal, decimal or hex numeral system to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
• Implement a TryParseByRadix extention method that onverts the string representation of a signed number in the octal, decimal or hex numeral system to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
  The task definition is given in the XML-comments for the methods.
  Restriction: Don't use Framework's converter classes.