More build fixes.
Changed the documentation builder to automatically prepend %EPOCROOT% (converted to a path relative form) to pre-processor include path options that start with 'epoc32'. Prevously $(EPOCROOT) was prepended in the makefile, which broke the documentation build because the pre-processor will only accecpt relative path include options.
THE MAIN PCRE LIBRARY
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Written by: Philip Hazel
Email local part: ph10
Email domain: cam.ac.uk
University of Cambridge Computing Service,
Cambridge, England.
Copyright (c) 1997-2008 University of Cambridge
All rights reserved
THE C++ WRAPPER LIBRARY
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Written by: Google Inc.
Copyright (c) 2007-2008 Google Inc
All rights reserved
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