Fix Adform's parameters regex (prebid#1214)

* Added adform info file

* Added Adform adapter and bidder

* Updates from master

* Removed usersyncInfo from Adform adapter. Inverted Imp type check.

* Removed excessive loop

* Updated with the last master

* Create readme file for adform

* Fix Adform's parameters regex

Motivation: catastrophic backtracking during regex execution

Details:
- https://regex101.com/r/NNQrWq/1
- string to check "url_domain:keskustelu.suomi24.fi,url_path:/matkailu/matkakohteet/aasia,layout:lg,categories:Matkailu,main_category:Matkailu"

Co-authored-by: v.statkevich <[email protected]>
Co-authored-by: Olga Linkevich <[email protected]>

static/bidder-params/adform.json

@@ -16,7 +16,7 @@
     "mkv": {
       "type": "string",
       "description": "Comma-separated key-value pairs. Forbidden symbols: &. Example: mkv='color:blue,length:350'",
-      "pattern": "^(\\s*|(([^,:&]*[^,:&\\s]+[^,:&]*)+:[^,:&]*,)*(([^,:&]*[^,:&\\s]+[^,:&]*)+:[^,:&]*,?))$"
+      "pattern": "^(\\s*|((\\s*[^,:&\\s]+\\s*:[^,:&]*)(,\\s*[^,:&\\s]+\\s*:[^,:&]*)*))$"
     },
     "mkw": {
       "type": "string",