DWARF 5 operations and DWARF5 location lists (#418)

DWARF 5 operations and DWARF5 location lists (#418)

* Test binary for DWARFv5 operations

* DWARFv5 ops, part 1: entry_value, const_type, deref_type

* DWARFv5 ops, part 2: regval_type, implicit_pointer, convert

* DWARFv5 loclists section parsing, take 1

* Foamtting fix

* Test fixes

* Lineprogram header file_entries with DWARFv5 now are indexable by string

* Excising the View column, if present, from GNU readelf..decodedline output

* Readelf test fixes

* Typo

* Formatting and comments

* More style fixes