docs: improve unique jsdocs (#439)

Author: ST-DDT

src/unique.ts

@@ -1,5 +1,8 @@
 import * as uniqueExec from './vendor/unique';
 
+/**
+ * Module to generate unique entries.
+ */
 export class Unique {
   // maximum time unique.exec will attempt to run before aborting
   maxTime = 10;
@@ -21,9 +24,21 @@ export class Unique {
   }
 
   /**
-   * unique
+   * Generates a unique result using the results of the given method.
+   * Used unique entries will be stored internally and filtered from subsequent calls.
    *
-   * @method unique
+   * @param method The method used to generate the values.
+   * @param args The arguments used to call the method.
+   * @param opts The optional options used to configure this method.
+   * @param opts.startTime The time this execution stared. This will be ignored/overwritten.
+   * @param opts.maxTime The time this method may take before throwing an error.
+   * @param opts.maxRetries The total number of attempts to try before throwing an error.
+   * @param opts.currentIterations The current attempt. This will be ignored/overwritten.
+   * @param opts.exclude The value or values that should be excluded/skipped.
+   * @param opts.compare The function used to determine whether a value was already returned.
+   *
+   * @example
+   * faker.unique(faker.name.firstName())
    */
   unique<Method extends (args: Args) => string, Args extends any[]>(
     method: Method,