Fix #24
The first commit:
- visual improvement with no behavior change
The second commit:
- removes a bunch of LOCs
- slightly change behavior and makes it standard
With this PR:

This change makes this button visually accented, and gives to users a
hint about the primary action.
This commit does not change behavior.
When Enter or Return is pressed the default button will be always
clicked. All buttons can always be clicked from the keyboard by pressing
spacebar when the button has focus.
Concept tACK https://github.com/bitcoin-core/gui/pull/39/commits/4227a8e1f3a4f94a5a4cb7adeecf967e14156bde https://github.com/bitcoin-core/gui/pull/39/commits/4ec49f8d1e25b330e6a0f79ae897d98d29ff32f9
While testing this, at first my intuition was to click the bottom down menu, but there we have no create address. When i locked closer, i wondered if we could change the bottom down text for show addresses.
from From Receiving addresses to Show all receiving addresses ? To indicate that we do not create there new addresses

Tested ACK 4ec49f8d1e25b330e6a0f79ae897d98d29ff32f9 on macos.
113 | @@ -114,6 +114,12 @@ 114 | <iconset resource="../bitcoin.qrc"> 115 | <normaloff>:/icons/receiving_addresses</normaloff>:/icons/receiving_addresses</iconset> 116 | </property> 117 | + <property name="autoDefault"> 118 | + <bool>false</bool> 119 | + </property>
I don't think we need to mess with this?
This change is required.
From Qt docs:
autoDefault : bool ... This property's default is true for buttons that have a QDialog parent; otherwise it defaults to false.
As ReceiveCoinsDialog is derived from QDialog its buttons have autoDefault == true by default.
Having autoDefault == true breaks rendering of the default button when tabbing through it (when it is focused out). At least on Linux Mint 20 with system Qt 5.12.8.
Weird, sounds like a Qt bug?
Maybe. Didn't track it down though.
utACK, minor nit
utACK