Update gpg keys

README.md

@@ -78,9 +78,10 @@ This will generate files named `bitcore.js` and `bitcore.min.js`.
 You can also use our pre-generated files, provided for each release along with a PGP signature by one of the project's maintainers. To get them, checkout a release commit (for example, https://github.com/bitpay/bitcore/commit/e33b6e3ba6a1e5830a079e02d949fce69ea33546 for v0.12.6).
 
 To verify signatures, use the following PGP keys:
-- @braydonf: https://pgp.mit.edu/pks/lookup?op=get&search=0x9BBF07CAC07A276D
-- @kleetus: https://pgp.mit.edu/pks/lookup?op=get&search=0x33195D27EF6BDB7F
-- @pnagurny: https://pgp.mit.edu/pks/lookup?op=get&search=0x0909B33F0AA53013
+- @braydonf: https://pgp.mit.edu/pks/lookup?op=get&search=0x9BBF07CAC07A276D `D909 EFE6 70B5 F6CC 89A3 607A 9BBF 07CA C07A 276D`
+- @gabegattis: https://pgp.mit.edu/pks/lookup?op=get&search=0x441430987182732C `F3EA 8E28 29B4 EC93 88CB  B0AA 4414 3098 7182 732C`
+- @kleetus: https://pgp.mit.edu/pks/lookup?op=get&search=0x33195D27EF6BDB7F `F8B0 891C C459 C197 65C2 5043 3319 5D27 EF6B DB7F`
+- @matiu: https://pgp.mit.edu/pks/lookup?op=get&search=0x9EDE6DE4DE531FAC `25CE ED88 A1B1 0CD1 12CD  4121 9EDE 6DE4 DE53 1FAC`
 
 ## License