Install gcal on dev and shell servers

Summary:
Allow to get more advanced option than base cal,
like for example week numbers with gcal -K

Test Plan:

$ gcal -K

     January 2019
 Su Mo Tu We Th Fr Sa CW
        1  2  3  4  5 52/0
  6  7  8  9 10 11 12 01
 13 14 15 16 17 18 19 02
 20 21 22 23 24 25 26 03
 27 28 29 30 31       04
`

Reviewers: dereckson

Differential Revision: https://devcentral.nasqueron.org/D2054