completed cachefile class, gitignore cachefiles

  -handles failure to open cachefile upon first run
 - verified functionality
 - yep
 - pops from cache stack once full
 - added cachefile type to gitignore
Merge branch 'cachefile' into develop

Conflicts:
	.gitignore

- new filenames for cache and config files (use the .splatfilch extension)
- fixed names in configmanagement, cachefile, and splatfilch main to conform to standard naming conventions (see issue #33)
- added new cache function to remove item if present