My very first advice to your first question is
DO NOT CHASE AFTER THE WIND. Your question has the tendency for chasing after the ghost.
Now if you just want the answer as a reference of the global trend, you can refer to
http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html.
However as a decade old developer working in the local enterprise stream, my take is the following not sorted since I have no empirical results to support this claim. So you take it with a pinch of salt.
Java, C#(.NET), Ruby, Python, Javascript
The above few programming languages would likely to get you entrenched for years in the enterprise software houses and projects.
Outside the list above, some emerging ones are Clojure, Scala, Groovy, Golang, Coffeescript, Typescript which you can take closer looks.
For your 2nd question, yes there will certainly be growth for developers in Singapore regardless of local or foreign talents. My observation is, there is really a lack of really good software developers. When I say really good software developers, I am referring to a versatile mature full stack developer whom embraces the frontier technological knowledge into web, network, storage, infrastructure, mobile, IoT, databases, distributed, architecting etc.
You will find lesser developers which are heavily desk bounded types which may be just good enough to code, but not versatile outside of understanding one or 2 programming languages + some knowledge in web technologies but mostly surface knowledge. Having myself has been a long time software developer, I don't see many of which I can truly admire for their skill sets. Good enough yes, really fantastically good that I can regard as someone I will look upon in awe, nope. Hence I say there are a lot of rooms for someone whom is passion about technology and willing to an good lots of efforts for it.
Programmers are working in a creative environment and they are creators. Hence innovation and creativeness is the essence of how we should survive in the industry. If you just need a job, then I'm afraid you will burn out very fast in this industry. If you are in for challenges, there are plentiful waiting for you daily. If you are good, you will love to confront challenges, not avoid it.