cosmetic changes + enter behavior (#126)

* remove trailing whitespace

* always submit password on enter

Moves the keypress logic for keypresses from if-else statements
to switches, adds non-contextual behavior on pressing enter

* wrap pam actions and handle errors at on spot

* init all of text struct in input_text()

This gets rid off valgrind warning on unitialized variables

src/inputs.c

@@ -115,6 +115,8 @@ void input_text(struct text* target, u64 len)
 	target->end = target->text;
 	target->visible_start = target->text;
 	target->len = len;
+	target->x = 0;
+	target->y = 0;
 }
 
 void input_desktop_free(struct desktop* target)