Fix SOURCES


Boring yet done; the remaining cases to fix now are roughly:
* filenames containing underscore (needs framework extension)
* .tar (needs framework extension)
* .zip (needs framework extension)

```
$ grep ^sources */*/*eb|grep %s|cut -d: -f2|sort|uniq -c|sort|head     
     10 sources = ['%s%s-src.tar.gz' % (name.lower(), version)]
     10 sources = ['%s_%s.tar.gz' % (name.lower(), '_'.join(version.split('.')))]
     10 sources = ['%s-%s.tar' % (name, version)]
     10 sources = ['%s-%s.zip' % (name.lower(), version)]
     11 sources = ['CP2K-%s.tar.gz' % version]
     16 sources = ['%sV%s.TAR.gz' % (name, version)]
      1 sources = ['CFX%s%s_LINX64-without_helpfiles.tar' % (name, ''.join(version.split('.')))]
      1 sources = ['cplex_studio%s.linux-x86-64.bin' % ''.join(version.split('.'))]
      1 sources = ['inspector_xe_%s.tar.gz' % version]
      1 sources = ['l_cproc_p_%s_intel64.tgz' % version]
```

Didn't look into the source_urls yet; that may require some look into pkgsrc ideas.