Modernize personas under-the-hood - The search

* Upgrade the used mozilla API from v1.5 to v3
* Ditch Neon for curl
* Get rid of the get-HTML-then-search-within craziness

It is much faster and smarter now:
* Fetches the search results at once in JSON format,
  instead of repetitively making http calls for each persona,
  and relying on an ever-changing HTML design
* Doesn't redownload and overwrite files each time, so it is
  much faster for the second time of the same search query

This patch handles the search part. A follow-up patch will
handle the apply part.

Change-Id: I703fc7b510799e8c205566cf5ffad2a81f12c4ea
Reviewed-on: https://gerrit.libreoffice.org/61449
Tested-by: Jenkins
Reviewed-by: Heiko Tietze <tietze.heiko@gmail.com>
Tested-by: Heiko Tietze <tietze.heiko@gmail.com>
Reviewed-by: Muhammet Kara <muhammet.kara@pardus.org.tr>

cui/Library_cui.mk

@@ -66,8 +66,11 @@ $(eval $(call gb_Library_use_externals,cui,\
 	boost_headers \
 	$(call gb_Helper_optional,OPENCL,\
 		clew) \
+    curl \
     icuuc \
     icu_headers \
+    orcus-parser \
+    orcus \
 ))
 ifeq ($(DISABLE_GUI),)
 $(eval $(call gb_Library_use_externals,cui,\