This commit introduces a lookup table which maps SIM Service Number to its description.
The mapping is defined in 3GPP TS 51.011 version 4.15.0 Release 4, 10.3.7 EF.SST (SIM Service Table)
Change-Id: I4a416bd8bff563ae08b1b3c053d2047da91667b4
pySim has been using magic numbers to access various files which makes it hard
to read, maintain and extend. With this file in place we can start replacing all
those magic numbers with human readable names lile EF['IMSI'] instead of
['3F00', '7F20', '6F07'].
Change-Id: I38f5d36d16b41b5d516a6a3e2ec1d09637883932