PSSE v35 file parsing bugs

[mcllerena]

• In a particular WECC psse case, there are branch type elements with similar IDs:

1234, 4321, '1 '
1232, 4321, ' 1'

messing with the parsing logic. A robust parsing approach should be implemented to avoid these issues.

• For parsing switching device types, the STYPE field is missing the number 1 type to be parsed. Right now we are doing it for 2 and 3 types, and fails when the type 1 appears.

The fix approach is implemented on a PR in PSY: Sienna-Platform/PowerSystems.jl#1664