update Search by use case GSoC idea description

Author: brenoferreira

content/gsoc-2019/project-ideas-collection/search-by-use-case/contents.lr

@@ -6,7 +6,7 @@ title: CC Search: search by use case
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 description:
 
-Prototype in CC Search a way to search for specific materials to use for specific types of projects.
+Prototype in CC Search a way to search for specific materials to use for specific types of projects. For example: search images for slide presentations (stock photos), for printed and/or digital magazines (which might require high resolution), for educational material (use content from GLAM providers), etc..
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 rationale: 
 
@@ -25,10 +25,10 @@ A new feature or set of new features added to CC Search to support searching CC-
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 skills_recommended: JavaScript, potentially Python
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-primary_mentor: Breno Ferreira
+primary_mentor: Alden Page
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-backup_mentor: Alden Page
+backup_mentor: Breno Ferreira
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-difficulty: Easy
+difficulty: Medium
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 proposal_tag: Search