Improving build instructions.

README.md

@@ -28,7 +28,7 @@ These instructions have proven to work on Ubuntu 20.4.
 ```
 sudo apt install git cmake g++ libssl-dev libmariadb-dev 
 sudo apt install libpq-dev libaprutil1-dev apache2-dev libboost-all-dev
-sudo apt install librdkafka-dev libmysqlclient-dev default-libmysqlclient-dev
+sudo apt install librdkafka-dev default-libmysqlclient-dev
 
 git clone https://github.com/stephb9959/poco
 cd poco
@@ -46,6 +46,24 @@ cmake ..
 cmake --build . --config Release
 sudo cmake --build . --target install
 
+cd ~
+git clone https://github.com/nlohmann/json.git
+cd json
+mkdir cmake-build
+cd cmake-build
+cmake ..
+make -j
+sudo make install
+
+cd ~
+git clone https://github.com/pboettch/json-schema-validator.git
+cd json-schema-validator
+mkdir cmake-build
+cd cmake-build
+cmake ..
+make -j
+sudo make install
+
 cd ~
 git clone https://github.com/Telecominfraproject/wlan-cloud-ucentralgw
 cd wlan-cloud-ucentralgw
@@ -53,6 +71,8 @@ mkdir cmake-build
 cd cmake-build
 cmake ..
 make
+
+
 ```
 
 ### Fedora