Merge #275: Fix up of Block Clock strings

5ccd6ae qml: fix capitalization on BlockClock Please wait string (johnny9)
518019f qml: use Estimating as the default string for remainingSyncTime (johnny9)

Pull request description:

  [![Windows](https://img.shields.io/badge/OS-Windows-green)](https://api.cirrus-ci.com/v1/artifact/github/bitcoin-core/gui-qml/win64/insecure_win_gui.zip?branch=pull/275)
  [![Intel macOS](https://img.shields.io/badge/OS-Intel%20macOS-green)](https://api.cirrus-ci.com/v1/artifact/github/bitcoin-core/gui-qml/macos/insecure_mac_gui.zip?branch=pull/275)
  [![Apple Silicon macOS](https://img.shields.io/badge/OS-Apple%20Silicon%20macOS-green)](https://api.cirrus-ci.com/v1/artifact/github/bitcoin-core/gui-qml/macos_arm64/insecure_mac_arm64_gui.zip?branch=pull/275)
  [![ARM64 Android](https://img.shields.io/badge/OS-Android-green)](https://api.cirrus-ci.com/v1/artifact/github/bitcoin-core/gui-qml/android/insecure_android_apk.zip?branch=pull/275)

ACKs for top commit:
  jarolrod:
    ACK 5ccd6ae

Tree-SHA512: 8eed140b96340c382bc47b170ec5e52879f21b6ed96f2bf63ccd7bde730361df7191a809f869c9ea76cdec1afa5ee6e1666d3637987059552908dc5d5c26cd49

Author: hebasto

src/qml/components/BlockClock.qml

@@ -131,7 +131,7 @@ Item {
                 target: root
                 header: "Connecting"
                 headerSize: 24
-                subText: "Please Wait"
+                subText: "Please wait"
             }
             PropertyChanges {
                 target: bitcoinIcon
@@ -176,6 +176,6 @@ Item {
             return "~" + seconds + (seconds === 1 ? " second" : " seconds") + " left";
         }
 
-        return "~0 seconds left";
+        return "Estimating";
     }
 }