Add tests

Closes #7 (closed)

src/api/__mocks__/users.js

+const users = [
+  { deactivated: false, id: '1', nickname: 'john', local: true },
+  { deactivated: false, id: '2', nickname: 'bob', local: false },
+  { deactivated: true, id: '3', nickname: 'allis', local: true }
+]
+
+export async function fetchUsers(showLocalUsersOnly, token, page = 1) {
+  const filteredUsers = showLocalUsersOnly ? users.filter(user => user.local) : users
+  return Promise.resolve({ data: {
+    users: filteredUsers,
+    count: filteredUsers.length,
+    page_size: 50
+  }})
+}
+
+export async function toggleUserActivation(nickname, token) {
+  const response = users.find(user => user.nickname === nickname)
+  return Promise.resolve({ data: { ...response, deactivated: !response.deactivated }})
+}
+
+export async function searchUsers(query, showLocalUsersOnly, token, page = 1) {
+  const filteredUsers = showLocalUsersOnly ? users.filter(user => user.local) : users
+  const response = filteredUsers.filter(user => user.nickname === query)
+  return Promise.resolve({ data: {
+    users: response,
+    count: response.length,
+    page_size: 50
+  }})
+}