add Calix E7 with module bays (#665)

device-types/Calix/E7-2.yaml

@@ -0,0 +1,15 @@
+---
+manufacturer: Calix
+model: E7-2
+slug: e7-2
+part_number: 000-00372
+u_height: 1
+is_full_depth: false
+comments: ''
+module-bays:
+  - name: slot 1
+    label: ''
+    position: '1'
+  - name: slot 2
+    label: ''
+    position: '2'

device-types/Calix/E7-20.yaml

@@ -0,0 +1,91 @@
+---
+manufacturer: Calix
+model: E7-20
+slug: e7-20
+part_number: 100-02089
+u_height: 13
+is_full_depth: false
+comments: ''
+interfaces:
+  - name: mgmt 1
+    type: 1000base-t
+    mgmt_only: true
+    label: ''
+    description: ''
+  - name: mgmt 3A
+    type: 1000base-t
+    mgmt_only: true
+    label: ''
+    description: ''
+  - name: mgmt 3B
+    type: 1000base-t
+    mgmt_only: true
+    label: ''
+    description: ''
+module-bays:
+  - name: slot 1
+    label: ''
+    position: '1'
+  - name: slot 2
+    label: ''
+    position: '2'
+  - name: slot 3
+    label: ''
+    position: '3'
+  - name: slot 4
+    label: ''
+    position: '4'
+  - name: slot 5
+    label: ''
+    position: '5'
+  - name: slot 6
+    label: ''
+    position: '6'
+  - name: slot 7
+    label: ''
+    position: '7'
+  - name: slot 8
+    label: ''
+    position: '8'
+  - name: slot 9
+    label: ''
+    position: '9'
+  - name: slot 10
+    label: ''
+    position: '10'
+  - name: slot 11
+    label: ''
+    position: '11'
+  - name: slot 12
+    label: ''
+    position: '12'
+  - name: slot 13
+    label: ''
+    position: '13'
+  - name: slot 14
+    label: ''
+    position: '14'
+  - name: slot 15
+    label: ''
+    position: '15'
+  - name: slot 16
+    label: ''
+    position: '16'
+  - name: slot 17
+    label: ''
+    position: '17'
+  - name: slot 18
+    label: ''
+    position: '18'
+  - name: slot 19
+    label: ''
+    position: '19'
+  - name: slot 20
+    label: ''
+    position: '20'
+  - name: slot A
+    label: ''
+    position: 'A'
+  - name: slot B
+    label: ''
+    position: 'B'