Protocol [LEVEL_0] reimplementation and remote access control;
Basic implementation of user groups data structures;
Groups.java file add;
Changing user index file format according to a2 specs;
Fix for remote login command;
Implementing new data structures in dirShema and dirEntry classes;
Fixing creation directories while first start of system;
Some improvements in networking subsystm;
<!> Applying new format of directories index;

Warning! <!> mark means that this commit hadn't been well tested. Be carefull!
<!> Some dirEntry class fields moved from using ArrayList to simple arrays;
<!> Fix for dirEntry.toCsv() method;
<!> Additional fixage for dirEntry.toCsv() method (NullPointerException occurred);
<!> Access checking code added (according to a2 specs);
<!> Changing javadoc generation options;
Implements new access model to protocol procedures;

This commit is stable enough for devel branch.
Removing support of 'RIBBON_SCTL_LOGIN' command;
Providing control autorization in system, renaming [LEVEL_0] RIBBON_CONNECTION_* to RIBBON_NCTL_*;
Dependency for libRibbonData added to project;
Complete of removing the anonymous mode from code;
Changes in main configuration properties file;