function readFiles( files ) {
		var count;
		var cache;
		var opts;
		var cb;
		var i;

		opts = {
			'encoding': 'utf8'
		};
		count = 0;
		cache = {};
		for ( i = 0; i < files.length; i++ ) {
			cb = onReadFactory( files[ i ], onData );
			readFile( files[ i ], opts, cb );
		}
		/**
		* Callback invoked upon reading a file.
		*
		* @private
		* @param {string} filename - filename
		* @param {string} data - content
		*/
		function onData( filename, data ) {
			cache[ filename ] = data;
			count += 1;
			if ( count === files.length ) {
				compileFiles( cache );
			}
		}
	}
Reads files.

@private
@param {StringArray} files - files to read