run tests without ts-node in order to speed up the build

[akosyakov]

ts-node is still used by:

• UI tests (get rid of ts-node in examples #4140)
• check-hoisting script (add check:hoisted command to theia cli #4138)

UI tests can be compiled to js before execution, the script can be rewritten with js or merged into theia CLI. It will improve the speed up as well + completely removing ts-node (and its dependencies) also will improve the speed.

[akosyakov]

It dropped the build time from 30m to 17m on travis mac.

[akosyakov]

I've split test execution in 3 separate travis scripts that on failure of browser tests all tests are not executed again together. Together with getting of ts-node it dropped Linux build to 18m from 30m.

Browser tests indeed takes only 1 min, but because instability they were executed 3 times by traivs: https://travis-ci.org/theia-ide/theia/jobs/482793895#L5534 Increasing the build time by 3mins, this time debug adapters were downloaded, it is completely internal wdio issue. //cc @marcdumais-work

I've noticed that the slowest unit tests are from extension-manager, since it is not used by anyone and we are going to get rid of it (replacing with plugin UI), i will disable all tests for this extension. It will save some minutes.

[akosyakov]

It's ready for the review. It's 14m instead 30m on Linux with all changes and if UI tests are stable.

[marcdumais-work]

this time debug adapters were downloaded, it is completely internal wdio issue.

We hope this PR will help stabilize the UI tests.

[svenefftinge]

LGTM

[marcdumais-work]

Test suites pass flawlessly locally on Linux. The Appveyor errors are the usual ones, not apparently made worse by this PR.