src/x2gokdrivehtmlclient.js: Send client keepalive ping every 10 seconds,...

See merge request x2go/client/html/x2gohtmlclient!2

src/x2gokdrivehtmlclient.js: Send client keepalive ping every 10 seconds, server expects at least one ping every 30 seconds.

debian/Jenkinsfile: Add file. Initiate CI builds.

See merge request x2go/client/html/x2gohtmlclient!1

conf/nginx/snippets/x2gohtmlclient-wswrapper.conf: Put regular expression into double-quotes. Otherwise nginx misinterprets the curly braces as config block braces.

{conf/nginx/,src/x2gohtmlclient.js}: Provide Nginx SSL configuration by default, switch back to wss:// protocol.

src/x2gohtmlclient.js: Switch to ws:// (unencrypted) for a start, SSL support for the complete package will be re-introduced soon.

src/x2gokdrivehtmlclient.js: Don't confuse syntax highlighters by putting unterminated quotes into comments.

  Also:

  - No capital letters in asset paths.
  - Shorten asset paths (esp. drop 'x2go-plugin/').

COPYING.{AGPL-3,GPL-2}: Add files. Web-files are licensed as AGPL-3+, other files (scripts, build stuff (in prep)) are licensed as GPL-2+).