On Win, do not always-append to cling-compiledata.h.in:

Before, cling-compiledata.h caused
```
interpreter\cling\lib\Interpreter\cling-compiledata.h(6,1): warning C4005: 'CLING_UCRT_VERSION': macro redefinition
  interpreter\cling\lib\Interpreter\cling-compiledata.h(3): message : see previous definition of 'CLING_UCRT_VERSION'
```
due to it containing
```

      #define CLING_INCLUDE_PATHS ""
      #define CLING_UCRT_VERSION  ""
      #define CLING_INCLUDE_PATHS ""
      #define CLING_UCRT_VERSION  "10.0.19041.0"
```

Tagging release v0.9

Tagging release v0.8

Tagging release v0.7

Tag cling release v0.6.

See https://github.com/root-project/cling/releases/tag/v0.6 for the release page

Tag cling release v0.5

Tagging release v0.4

Tag release v0.3

Tag a new version 0.2

Tagging version 0.1.