adding redirect url with spaces can brake sites

[nikolastanin]

Steps to reproduce:

• add a new redirect : "/education/custom-programs?utm_campaign=Custom program&utm_source=ppc&utm_medium=landing page&utm_term=AdWords&utm_content=cpc" that contains blank spaces in URL
• save and view site

expected result:

• site loads
• correct rule added to .htaccess: "RewriteCond %{QUERY_STRING} (^|&)utm_campaign=Custom\ program(&|&)utm_source=ppc(&|&)utm_medium=landing\ page(&|&)utm_term=AdWords(&|&)utm_content=cpc(&|$)"

actual result:

• site 500 error
• wrong rule added to .htaccess : "RewriteCond %{QUERY_STRING} ^utm_campaign=Custom program&utm_source=ppc&utm_medium=landing page&utm_term=AdWords&utm_content=cpc$"

root cause:

The plugin adds a wrongly formatted redirect rule to .htaccess, and Apache can't read it