Issue#36: .deb deploys default TLS certificate and private key (#39)

* issue#36: Generating TLS key and self-signed cert after installing/upgrading the package

* issue#36: Updated libstdc++.a dependency to v10

* issue#36: Generate self-signed certs after install/upgrade

* issue#36: Updated dependencies

* issue#36: Check for pre-existence of key/cert

build/binding.gyp.patch

@@ -1,10 +1,10 @@
---- /tmp/binding.gyp	2018-07-07 14:38:23.884143337 +0800
-+++ ../src/node_modules/argon2/binding.gyp	2018-07-07 14:39:09.684840870 +0800
+--- ../src/node_modules/argon2/binding.gyp
++++ ../src/node_modules/argon2/binding.gyp
 @@ -47,6 +47,7 @@
        ],
        "cflags+": ["-Wno-cast-function-type"],
        "include_dirs+": ["<!(node -e \"require('nan')\")"],
-+      "libraries": ["/usr/lib/gcc/x86_64-redhat-linux/9/libstdc++.a"],
++      "libraries": ["/usr/lib/gcc/x86_64-redhat-linux/10/libstdc++.a"],
        "dependencies": ["libargon2"],
        "configurations": {
          "Debug": {