Load all fixture grammars dynamically

This way the build doesn't take forever any time a single grammar has 
been regenerated.

cli/src/generate/nfa.rs

@@ -55,10 +55,6 @@ impl CharacterSet {
         CharacterSet::Include(Vec::new())
     }
 
-    pub fn all() -> Self {
-        CharacterSet::Exclude(Vec::new())
-    }
-
     pub fn negate(self) -> CharacterSet {
         match self {
             CharacterSet::Include(chars) => CharacterSet::Exclude(chars),
@@ -182,6 +178,7 @@ impl CharacterSet {
         }
     }
 
+    #[cfg(test)]
     pub fn contains(&self, c: char) -> bool {
         match self {
             CharacterSet::Include(chars) => chars.contains(&c),

cli/src/generate/properties.rs

@@ -464,7 +464,8 @@ fn parse_property_sheet(path: &Path, css: &str) -> Result<Vec<Rule>> {
             rsass::Item::AtRule { name, args, .. } => match name.as_str() {
                 "schema" => {
                     if let Some(s) = get_sass_string(args) {
-                        let schema_path = resolve_path(path, s)?;
+                        // TODO - use schema
+                        let _schema_path = resolve_path(path, s)?;
                         items.remove(i);
                         continue;
                     } else {