c: Add parsing support for indexing/addrof/deref/etc. operators and calls
Remove unnecessary is_leftassoc fields from operator precedence tables
Remove TODO entry for defined()

Having DEFINED() and the ID it's used on as separate ASTNODEs is nice
because it allows them to have their own locations, so we can show errors
on the ID in a DEFINED() instead of the whole DEFINED().
tk: Remove left-over token info field
ast: Beautify TK node dumping
Handle escape sequences in lexer, allow strings as atomic expressions
Show preset file name that's being processed
presets: Allow dropping #defines/#undefs after PP before C parsing

Especially useful for #defines that can't be parsed as C expressions.