increase maximum users in eNodeB to 16

some changes in logging for XFORMS and UL scheduling (activation in all subframes and retransmissions only via PHICH)

Work with virtual interfaces, you will have to set the eNB virtual interfaces up yourself (ifconfig ethx:y ipv4@ up)

handling of timing advance is improved. MAC retrieves timing advance from phy once prior to DL scheduling and clears the statistic in PHY. A timer for controlling the timing advance periodicity was introduced.

 - added -a option to lte-softmodem for easier testing of different RF chains
 - added $OPENAIR_TARGETS/bin to path for easier access to init scripts

minor changes in openair_device structure (naming of fields), calibration information for X310 timing, some initializations from lte-softmodem.c for USRP moved to usrp_lib.cpp

adding compiled firmware that supports TDD (corresponding openair0 svn revision 6313)

added support for TDD for EXMIMO