2.0 - 2020-10-22
	- [BREAKING CHANGE] Variables are now globally scoped
	- Completely rewritten in C
	- Add support for braces around pre_if conditions
	- Add support for nested macros
	- Variables and macros can be conditionally defined with pre_if
	- Add file context to error messages
	- More tests

1.2 - 2018-02-23
	- Preserve original string quoting and variable formatting
	- Fix parser to be more lenient with argument formats
	- Fix handling of the \\-escape sequence
	- Fix handling of quoting & parenthesis in 'if' directive
	- Fix handling of empty string in pre_if
	- Remove support for parenthesis around pre_if arguments

1.1 - 2018-01-24
	- Add pre_warn directive
	- Add -i/-o/-v/-h command line arguments
	- Add support for custom pre_include search paths (-I flag)
	- Fix handling of some common custom block directives (e.g. 'types')

1.0 - 2018-01-19
	- Initial version
