(Bug 45732) Set custom bold and italic buttons for Galician language

Use N for Bold (Negra) and C for Italic (Cursiva)

Change-Id: I89423dfb5b52065bb4bd25f2a54a6b2ef8e982ea
Localisation updates from http://translatewiki.net.

Change-Id: I51df828cf655c3baf648689135d26fbc126b9ede
Localisation updates from http://translatewiki.net.

Change-Id: Ice4b978f06dfdf046b793f3fab9f0505aede570f
Localisation updates from http://translatewiki.net.

Change-Id: I9d0c5f9bd600e5b22ab7de49f46a6d6f3fe58313
Merge branch 'master' of https://github.com/wikimedia/mediawiki-extensions-WikiEditor