Fix typo and missing I10n identifier for 2 strings
Fix bug when pcbnew is launched from a folder containing an existing fp-lib-table file by using same method as setting the initial global symbol library table. Fixes lp:1810169 https://bugs.launchpad.net/kicad/+bug/1810169 Fixes lp:1738871 https://bugs.launchpad.net/kicad/+bug/1738871