Update Readme with some links to the wiki and forums
Merge pull request #65 from Bigpet/master

Update Readme with some links to the wiki and forums
Directory-related functions implemented

* cellFsOpendir, cellFsReaddir, cellFsClosedir functions implemented.
* vfsDirBase: m_entryes, GetEntryes renamed to m_entries, GetEntries
respectively.
* vfsLocalDir: Read() function added to get the entries one by one.
* Moved IsExists() from vfsLocalDir to vfsDirBase to avoid "R6025 pure
virtual function call" error.
* Other minor changes in some functions of sys_fs
Few module functions added

Implemented:
* cellSysutilApGetRequiredMemSize
* cellGameContentErrorDialog

Binded lv2 SysCall 814 to cellFsUnlink