Versioning (#568)

- removed getClientServerAPIVersion in server (not used)
- removed rxr side (clientversion compatibility check), removed enum as well as it is now done on the client side.
- versionAPI.h
   - GITBRANCH changed to RELEASE
   - dates for all API changed to "sem_version date". Scripts to compile servers modified for this. Empty "branch" name will end up with developer for sem_version.

- Version class with constructor taking in the long version (APILIB date). Other member functions including concise(to get sem_version for new releases and date for old releases), 
  
- bypassing initial tests, also now bypasses the client-rxr compatibility check (at rx_hostname command)

- previously, compatibility between client-det was ensuring both had the same detector API (eg. same APIJUNGFRAU)
   - Now, compatibility only checks APILIB (client side) and detector API(eg. APIJUNGFRAU) (detector side) have same major version. It only does backward compatibility test. Rest is upto user to ensure. 
   - If server is from an older release, it will compare dates like previous implementation (APIJUNGFRAU from both client and det)
 
- - previously, compatibility between client-rxr was ensuring both had the same APIRECEIVER
   - Now, compatibility only checks APILIB (client side) and APIRECEIVER (rxr side) have same major version. It only does backward compatibility test. Rest is upto user to ensure. 
   - If rxr is from an older release, it will compare dates like previous implementation (APIRECEIVER from both client and rxr)

- removed APIGUI, evalVersionVariables.sh, genVersionHeader.sh (not needed or not used)

- clientVersion, rxrversion and detectorserverversion all return strings and not integers (in hex) anymore. Depending if it has semantic versioning, it will print that or the date if it is too old.

- fixed in python (strings for versions)
- check_version function in detector server changed to "initial checks" as it only checks server-firmware compatibility and initial server checks. Client compatibilities are moved to client side.
- --version gives sem_version and date? Is date needed as well. The clientversion, detserverversion and rxrversion API gives only sem_version (no date)
- - formatting

updateAPIVersion.sh

@@ -1,8 +1,9 @@
 # SPDX-License-Identifier: LGPL-3.0-or-other
 # Copyright (C) 2021 Contributors to the SLS Detector Package
-#require 2 arguments, API_NAME API_DIR (relative to package)
+usage="\nUsage: updateAPIVersion.sh [API_NAME] [API_DIR] [API_BRANCH(opt)]."
+
 if [ $# -lt 2 ]; then
-    echo "Wrong usage of updateVersion.sh. Requires atleast 2 arguments [API_NAME, API_DIR]"
+    echo -e "Requires atleast 2 arguments. $usage"
     return [-1]
 fi
 
@@ -12,6 +13,11 @@ API_DIR=$PACKAGE_DIR/$2
 API_FILE=$PACKAGE_DIR/slsSupportLib/include/sls/versionAPI.h
 CURR_DIR=$PWD
 
+if [ ! -d "$API_DIR" ]; then
+    echo "[API_DIR] does not exist. $usage"
+    return [-1]
+fi
+
 #go to directory
 cd $API_DIR
 
@@ -38,8 +44,22 @@ API_DATE=${API_DATE:2:6}
 API_DATE=${API_DATE/#/0x}
 echo "date="$API_DATE
 
+
+# API_VAL concatenates branch and date
+API_VAL=""
+# API branch is defined (3rd argument)
+if [ $# -eq 3 ]; then
+    API_BRANCH=$3
+    echo "branch="$API_BRANCH
+    API_VAL+="\"$API_BRANCH $API_DATE\""
+else
+    # API branch not defined (default is developer)
+    echo "branch=developer"
+    API_VAL+="\"developer $API_DATE\""
+fi
+
 #copy it to versionAPI.h
-echo "#define "$API_NAME $API_DATE >> $API_FILE
+echo "#define "$API_NAME $API_VAL >> $API_FILE
 
 #go back to original directory
 cd $CURR_DIR