Upgrade from peg 0.1.4 to peg 0.1.9
Merge pull request #20 from rekado/upgrade-peg

Upgrade from peg 0.1.4 to peg 0.1.9
Removed unneeded peg-memory-fix.patch.
Fix makefile to build peg, remove peg-exe-ext.patch
Refactoring to build on windows

all .c files now build as separate files.
code has been refactored to not depend on inclusion of .c files
functions in utility_functions.c are now extern
removed strdup and strcasecmp prototypes, now use .h files
fixed inconsistent linkages in markdown_output.c
Fixed distclean so it doesn't wipe out peg directory.
Removed optimization flag that requires newer GCC.
Only obfuscate ascii characters.

See fletcher/peg-multimarkdown/issues/139 for background.
Treat <head> as block-level HTML tag.

Closes #21.
Merge branch 'upstream' into strike-extension
add instructions for strike-through extension
Do not print "\usepackage{}" line

The generated LaTeX output is understood to be the document body,
so it may not contain macros that belong into the preamble.