HPCC-9723 change Package name to allow multiple clienttools installed

change ClientTools package name to "hpccsystems-clienttools-<major version>.<mintor version>
This will allow multiple clienttools with different <major version>.<mintor version> installed
on the systems. For example following clienttools can co-exist on a system:
   hpccsystems-clienttools-4.0_community-4.0.2-2el6_x86_64.rpm
   hpccsystems-clienttools-4.2_community-4.2.0-1el6_x86_64.rpm

On the other hand if <major version>.<mintor version> are the same the newer package can be updated
on the top of older package. for example,
1) With different pack number:
   hpccsystems-clienttools-4.2_community-4.2.2-1el6_x86_64.rpm can be updated on top of
   hpccsystems-clienttools-4.2_community-4.2.0-1el6_x86_64.rpm

2) With different build(sequence) number
   hpccsystems-clienttools-4.2_community-4.2.0-2el6_x86_64.rpm can be updated on top of
   hpccsystems-clienttools-4.2_community-4.2.0-1el6_x86_64.rpm
HPCC-9723 Add PACKAGE_FILE_NAME_PREFIX

Add a new varialbe PACKAGE_FILE_NAME_PREFIX in top level CMakeLists.txt which will have pacakge
name without version information. It is used for creating CPACK_PACKAGE_FILE_NAME
Merge pull request #4912 from xwang2713/Ming_HPCC_9723_3

HPCC-9723 change Package name to allow multiple clienttools installed

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>