Merge branch 'update-readme' into 'master'

Update README.md

See merge request !3

README.md

 # PMT: Power Measurement Toolkit
-
 PMT is a high-level software library capable of collecting power consumption measurements on various hardware. The library provides a standard interface to easily measure the energy use of devices such as CPUs and GPUs in critical application sections.
 
 # Installation
@@ -7,17 +6,61 @@ First clone the repository:
 ```
 git clone --recursive git@git.astron.nl:RD/pmt.git
 ```
-
 The `--recursive` flag makes sure that the git submodules are also cloned. If you cloned the repository without this flag, you can initialize the submodules as follows:
 ```
 git submodule update --init
 ```
-`
+To build the software, run the following commands:
+1. Set-up cmake in a build directory and cd into the directory, e.g. `~/pmt/build`
+     * `cmake <source dir path> -DCMAKE_INSTALL_PREFIX=<install dir path>`
+2. Optionally further configure cmake through interactive build settings or with command line variables
+     * use `ccmake` and/or add `-DBUILD_<SENSOR>_PMT=<0 or 1>` to the `cmake` commandline to select which PMT are built.
+3. make and install
+     * `make install`
 
 # Usage
+Include the header file into your program, e.g.:
+```
+#include “pmt.h”
+```
+Depending on which PMT implementations you have selected during the build, you can now initialize
+any PMT instance:
+```
+std::unique ptr<pmt::PMT> sensor(pmt::nvml::NVML::create());
+```
+Next, you can start measuring power using the common api as specified in `pmt.h`:
+```
+pmt::State start, end;
+start = sensor−>read();
+...
+end = sensor−>read () ;
+std::cout<<sensor−>joules(start, end) <<” [J]“<<std::endl;
+std::cout<<sensor−>watts(start, end) <<” [W]“<<std::endl;
+std::cout<<sensor−>seconds(start, end)<<” [S]“<<std::endl;
+```
 
 # pmt-test
+PMT-test executables might be used direclty to read the values of a PowerSensor at a regular interval. The PMT-test executables are available in the install directory `/bin`.
 
+# Acknowledgement
+If you decide to use PMT in your research, please cite the following reference:
 
-# Ack
+```
+@misc{https://doi.org/10.48550/arxiv.2210.03724,
+  doi = {10.48550/ARXIV.2210.03724},
+  
+  url = {https://arxiv.org/abs/2210.03724},
+  
+  author = {Corda, Stefano and Veenboer, Bram and Tolley, Emma},
+  
+  keywords = {Performance (cs.PF), FOS: Computer and information sciences, FOS: Computer and information sciences},
   
+  title = {PMT: Power Measurement Toolkit},
+  
+  publisher = {arXiv},
+  
+  year = {2022},
+  
+  copyright = {arXiv.org perpetual, non-exclusive license}
+}
+```