Code/repo search (#2582)

Indexed search of repository contents (for default branch only)

conf/app.ini

@@ -192,7 +192,11 @@ ITERATE_BUFFER_SIZE = 50
 
 [indexer]
 ISSUE_INDEXER_PATH = indexers/issues.bleve
+; repo indexer by default disabled, since it uses a lot of disk space
+REPO_INDEXER_ENABLED = false
+REPO_INDEXER_PATH = indexers/repos.bleve
 UPDATE_BUFFER_LEN = 20
+MAX_FILE_SIZE = 1048576
 
 [admin]
 ; Disable regular (non-admin) users to create organizations