Use import = require syntax to resolve "Circular definition" error with esModuleInterop

[jekh]

When using typescript 2.7 with --esModuleInterop, typescript gives this error when using ts-mockito:

node_modules/ts-mockito/lib/ts-mockito.d.ts(39,8): error TS2303: Circular definition of import alias 'mockito'.

Switching to the typescript-specific import = require-style import fixes this issue and is compatible with the non-esModuleInterop setting as well. It's the same solution that was used to address another interop-related issue in microsoft/TypeScript#21535

Is there a reason ts-mockito.ts needs to self-import? That seems like it might have other unintended consequences.

[bendykowski]

Hi @jekh, thank you for this PR. What do you think about the solution proposed by @jjordan-dff in #69? I think that one would be much cleaner for what guys wanted to achieve here. A default export was introduced to satisfy ember-browserify library.

[jekh]

#69 would be great, and personally I think it's cleaner than the self-import. I'll close this PR in favor of that one. Thanks for taking a look!