web-search: add wolframalpha search engine (#8638)

plugins/web-search/README.md

@@ -39,6 +39,7 @@ Available search contexts are:
 | `qwant`               | `https://www.qwant.com/?q=`              |
 | `givero`              | `https://www.givero.com/search?q=`       |
 | `stackoverflow`       | `https://stackoverflow.com/search?q=`    |
+| `wolframalpha`        | `https://wolframalpha.com/input?i=`      |
 
 Also there are aliases for bang-searching DuckDuckGo:
 

plugins/web-search/web-search.plugin.zsh

@@ -19,6 +19,7 @@ function web_search() {
     qwant       "https://www.qwant.com/?q="
     givero      "https://www.givero.com/search?q="
     stackoverflow  "https://stackoverflow.com/search?q="
+    wolframalpha   "https://www.wolframalpha.com/input/?i="
   )
 
   # check whether the search engine is supported
@@ -55,6 +56,7 @@ alias goodreads='web_search goodreads'
 alias qwant='web_search qwant'
 alias givero='web_search givero'
 alias stackoverflow='web_search stackoverflow'
+alias wolframalpha='web_search wolframalpha'
 
 #add your own !bang searches here
 alias wiki='web_search duckduckgo \!w'