Update teams to remove two Sass folks and add new Core member

docs/_data/core-team.yml

@@ -0,0 +1,19 @@
+- name: Mark Otto
+  user: mdo
+  gravatar: bc4ab438f7a4ce1c406aadc688427f2c
+
+- name: Jacob Thornton
+  user: fat
+  gravatar: a98244cbdacaf1c0b55499466002f7a8
+
+- name: Chris Rebert
+  user: cvrebert
+  gravatar: edec428c425453955f770095a7d26c50
+
+- name: Julian Thilo
+  user: juthilo
+  gravatar: 0f7dd3ce58a416be5685ea6194f82b11
+
+- name: XhmikosR
+  user: xhmikosr
+  gravatar: e37759b1ea0125d4e97b1e00b5eed26f

docs/_data/sass-team.yml

@@ -0,0 +1,7 @@
+- name: Thomas McDonald
+  user: mdo
+  gravatar: 24cd55ab1a62ffb113ab8c02f64c9301
+
+- name: Gleb Mazovetskiy
+  user: glebm
+  gravatar: 729f685b8e8d7e9feed18c177c82e59b