Friendly group name to display group names with spaces

[angcast]

Previously, when a person tried to input a group name with spaces, it would not work. Now with this change, this is possible. If a person writes a name with spaces, the name attribute in the Group model will replace the spaces with underscores. Meanwhile, the friendly_name attribute will keep the spaces and use this to display the name with the spaces in the frontend.

[soyapark]

Hi Angie!

I try to hit the "create" button and no matter if I have spaces or not I run into this following error from my web console.

[Error] TypeError: $("#group-name").val().replaceAll is not a function. (In '$("#group-name").val().replaceAll(' ','_')', '$("#group-name").val().replaceAll' is undefined)
	(anonymous function) (create_group.js:9)
	dispatch (jquery.min.js:3:8442)
	handle (jquery.min.js:3:5145)

[soyapark]

Also, we might want to say in the interface that space is allowed?

murmur/browser/templates/murmur/edit_create_group.html

Line 15 in 7261e87

Maximum 20 characters. Only alphanumeric characters, underscores, and dashes allowed.

[soyapark]

Can you retract this change? .env.example is meant to be a template