main.rb [options] expressions_file
-u, --uri [URI] URI to reverse polish notation API
By default localhost api uri will be used http://127.0.0.1:8000
expressions_file should be in form:
<num of expressions>
<expression1>
<expression2>
...
STDOUT will be in form:
<result1> <calculation time 1>
<result2> <calculation time 1>
...