Remove deprecated functions from api.ts (aka client.ts) (#1534)

* Removed deprecated functions from client.ts

* Renamed files to be camelCase

* Created top-level utils folder and tied all sub-references to it

* Grouped tests for those utils into their own section

Co-authored-by: Nathan Nichols <natenichols@cox.net>

test/utils/signPaymentChannelClaim.ts

@@ -0,0 +1,26 @@
+import {assertResultMatch} from '../testUtils'
+import responses from '../fixtures/responses'
+import signPaymentChannelClaim from '../../src/utils/signPaymentChannelClaim'
+
+
+
+describe('signPaymentChannelClaim', function () {
+  it('basic signature matches', () => {
+    
+    const channel = "3E18C05AD40319B809520F1A136370C4075321B285217323396D6FD9EE1E9037"
+    const amount = ".00001"
+    const privateKey = 'ACCD3309DB14D1A4FC9B1DAE608031F4408C85C73EE05E035B7DC8B25840107A'
+    
+    const result = signPaymentChannelClaim(
+      channel,
+      amount,
+      privateKey
+    )
+    
+    assertResultMatch(
+      result,
+      responses.signPaymentChannelClaim,
+      'signPaymentChannelClaim'
+    )
+  })
+})