refactor: link libvieter; remove cron code & daemon

This giant commit removes the old cron daemon & parser, replacing the
latter with a C implementation that will now be maintained in a separate
C library that gets developed independently. This commit lays the
groundwork for implementing features of Vieter in C where possible.

.editorconfig

@@ -5,6 +5,5 @@ root = true
 end_of_line = lf
 insert_final_newline = true
 
-[*.v]
-# vfmt wants it :(
+[*.{v,c,h}]
 indent_style = tab