fix bug with exporting elf, fix bug with symbol name containing a trailing \0,...

fix bug with exporting elf, fix bug with symbol name containing a trailing \0, and add a new method that returns all the symbols ids and names
3 jobs for master in 4 minutes and 14 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #865022112
build

00:02:30

 
  Test
passed #865022113
test

00:01:44

21.0%
 
  External
passed continuous-integration/appveyor/branch