Added a text file describing the debug file format.
Fixed misleading transposition in the comment describing FILE_LINE_SCALE_FACTOR.
Minor cleanup to the debug file format specification.
Revised format specification after looking through the compiler source code.
Debug information patch, but without code cleanup.
Fixed comments that weren't fully updated for the debug information patch.
Code cleanup for the debug information patch.
Corrected spelling error in artificial identifiers for superseded replacement routines.
Added missing guards to prevent attempts to write debug information when none was requested.
Made character numbers and file positions mandatory in debug information files.
Added missing type subelement to table entries for grammar lines.
Merge pull request #4 from EmacsUser/xml-debug-file-format

Patch to emit debug information files in a new XML format