pgAdmin 4 commit: Added the license information about the file-manager

Added the license information about the file-manager (repository:
https://github.com/simogeo/Filemanager), which we used to derive our own
version of it as per our requirement.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=0ecfbab129831811ce1c2616bfef5a039a64078f
Author: Surinder Kumar <surinder.kumar@enterprisedb.com>

Modified Files
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libraries.txt | 1 +
1 file changed, 1 insertion(+)