Move to Bootstrap 4

Bootstrap < 4.1.2 has the following CVE:
https://nvd.nist.gov/vuln/detail/CVE-2018-14041

Removed bootstrap-theme.css due to "Replaced the separate optional
theme with configurable options via SCSS variables
(e.g., $enable-gradients: true)."

Added "width: 100%" to a few places where width 100% was no longer
getting inherited.
Moved a few elements and adjusted styles to get the same look as
before.

See https://getbootstrap.com/docs/4.0/migration/ for more
information.

Tested: Manually on a Witherspoon.
Change-Id: I0a72665ac1ca6eacd0b553a585b1fb15e14ae62c
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/app/users/styles/user-accounts.scss b/app/users/styles/user-accounts.scss
index 914388a..891b3a9 100644
--- a/app/users/styles/user-accounts.scss
+++ b/app/users/styles/user-accounts.scss
@@ -1,7 +1,9 @@
 $userInputHeight: 40px;
 
 .user-manage__form {
+  width: 100%;
   label {
+    width: 100%;
     min-width: 210px;
     font-weight: 700;
     margin-right: 4em;