Update requirements.txt

requirements.txt

-Flask==0.12.4
-werkzeug<0.15
-Flask-Login==0.4.1
-Flask-Bower==1.3.0
-Flask-Babel==0.11.2
-Flask-WTF==0.14.2
-flask-restplus==0.10.1
-Flask-Caching==1.4.0
-WTForms==2.1
-arrow==0.13.0
-pluginbase==0.5
-tzlocal==1.5.1
-six==1.11.0
-pyOpenSSL>=17.5.0
-configobj==5.0.6
+Flask>=1.1.4
+werkzeug>=2.0.2
+Flask-Login>=0.4.1
+Flask-Bower>=1.3.0
+Flask-Babel>=0.11.2
+Flask-WTF>=0.14.3
+flask-restplus>=0.10.1
+Flask-Caching>=1.10.1
+WTForms>=2.3.3
+arrow>=0.13.0
+pluginbase>=0.5
+tzlocal>=1.5.1
+six>=1.11.0
+pyOpenSSL>=20.0.1
+configobj>=5.0.6
 pyasn1>=0.2.3
 cffi>=1.10.0
-backports.functools_lru_cache==1.2.1
+backports.functools_lru_cache>=1.2.1