synchronized boolean hasEntry(String md5) {
		FileCacheEntry fce = memCache.get(md5);
		if (fce == null) {
			fce = getFileByMD5(md5);
		}
		return fce != null;
	}
Deletes all stored files from this file cache that are under a "NN" two hex digit
nesting dir.
<p>
Will cause other processes which are accessing or updating the cache to error.
Ghidra/Features/Base/src/main/java/ghidra/formats/gfilesystem/FileCache.java