fix build_oai

- the option --UE was abused! Let's introduce --UE-conf-nvram and
  --UE-gen-nvram
- the option name --UE-OUTPUT was not clear and is now replaced by
  --UE-gen-nvram
- the new options are described when running ./build_oai -h
- print_help has been modified (' replaced by ") to print
  $conf_nvram_path and $gen_nvram_path

cmake_targets/build_oai

@@ -57,17 +57,20 @@ CMAKE_BUILD_TYPE=""
 UE_AUTOTEST_TRACE="False"
 trap handle_ctrl_c INT
 
+gen_nvram_path=$OPENAIR_DIR/targets/bin
+conf_nvram_path=$OPENAIR_DIR/openair3/NAS/TOOLS/ue_eurecom_test_sfr.conf
+
 function print_help() {
-  echo_info '
+  echo_info "
 This program installs OpenAirInterface Software
 You should have ubuntu 14.xx, updated, and the Linux kernel >= 3.14
 Options
 -h
    This help
 -c | --clean
-   Erase all files to make a rebuild from start"
+   Erase all files to make a rebuild from start
 -C | --clean-all
-   Erase all files made by previous compilations, installations"
+   Erase all files made by previous compilations, installations
 --clean-kernel
    Erase previously installed features in kernel: iptables, drivers, ...
 -I | --install-external-packages
@@ -83,6 +86,10 @@ Options
    Makes the LTE softmodem
 --UE
    Makes the UE specific parts (ue_ip, usim, nvram) from the given configuration file
+--UE-conf-nvram [configuration file]
+   Specify conf_nvram_path (default \"$conf_nvram_path\")
+--UE-gen-nvram [output path]
+   Specify gen_nvram_path (default \"$gen_nvram_path\")
 --RRH
    Makes the RRH
 -a | --agent
@@ -97,7 +104,7 @@ Options
    ETHERNET , None
    Adds this trasport protocol support in compilation
 --oaisim
-   Makes the oaisim simulator. Hardware will be defaulted to "None".
+   Makes the oaisim simulator. Hardware will be defaulted to \"None\".
 --phy_simulators
    Makes the unitary tests Layer 1 simulators
 --core_simulators
@@ -140,15 +147,12 @@ Usage (first build):
 Usage (Regular):
  oaisim : ./build_oai --oaisim -x 
  Eurecom EXMIMO + OAI ENB : ./build_oai --eNB -x 
- NI/ETTUS B201  + OAI ENB : ./build_oai --eNB -x -w USRP'
+ NI/ETTUS B201  + OAI ENB : ./build_oai --eNB -x -w USRP"
 }
 
 
 function main() {
 
-  local gen_nvram_path=$OPENAIR_DIR/targets/bin
-  local conf_nvram_path=$OPENAIR_DIR/openair3/NAS/TOOLS/ue_eurecom_test_sfr.conf
-
   until [ -z "$1" ]
   do
     case "$1" in
@@ -186,14 +190,11 @@ function main() {
        --UE)
             UE=1
             echo_info "Will compile UE"
-            shift
-            if test -n "$1"
-            then
-                [ -f "$1" ] || echo_fatal "file invalid for --UE"
+            shift;;
+       --UE-conf-nvram)
             conf_nvram_path=$(readlink -f "$1")
-                shift 1
-            fi;;
-        --UE-OUTPUT)
+            shift 2;;
+        --UE-gen-nvram)
             gen_nvram_path=$(readlink -f $2)
             shift 2;;
        --RRH)