Incorrect Grammar fix

Improve the grammar of the Dev donation setting.

xmrstak/donate-level.hpp

 #pragma once
 
 /*
- * Dev donation.
- * Percentage of your hashing power that you want to donate to the developer, can be 0.0 if you don't want to do that.
- * Example of how it works for the default setting of 2.0:
- * You miner will mine into your usual pool for 98 minutes, then switch to the developer's pool for 2.0 minute.
- * Switching is instant, and only happens after a successful connection, so you never loose any hashes.
+ * DEV DONATION SETTING
+ * This setting is a percentage of your hashing power that the miner donates to the developers of this app.
+ * It can be 0.0 if you don't want to help the developers. The default setting of 2.0 means that
+ * the miner will mine into your usual pool for 98 minutes, then switch to the developer's pool for 2.0 minutes.
+ * Switching pools is instant and it only happens after a successful connection, so you don't lose any hash time.
  *
- * If you plan on changing this setting to 0.0 please consider making a one off donation to our wallets:
+ * If you plan on changing this setting to 0.0, please consider making a one time donation to our wallets:
  * fireice-uk:
  * 4581HhZkQHgZrZjKeCfCJxZff9E3xCgHGF25zABZz7oR71TnbbgiS7sK9jveE6Dx6uMs2LwszDuvQJgRZQotdpHt1fTdDhk
  * psychocrypt:
  * 43NoJVEXo21hGZ6tDG6Z3g4qimiGdJPE6GRxAmiWwm26gwr62Lqo7zRiCJFSBmbkwTGNuuES9ES5TgaVHceuYc4Y75txCTU
  *
+ * Thank you for your support.
  */
 
 constexpr double fDevDonationLevel = 2.0 / 100.0;