Installer errors handling clean up

Installer errors handling clean up

[Issue#]       LINUXWRT-100
[Bug]          Unused error code, too much code error enums in overall
[Cause]        Development
[Solution]     Error handling will be clean up.

Error handling of installer after modifications will look in following way:
-    each job declares it's on exceptions (DECLARE_JOB_EXCEPTION) that can be used in it's tasks (jobs/(job)/(job)_errors.h),
-    each exception have associated enum Exceptions::Type value (many exceptions can have same value),
-    Exceptions::Type enum value is translated into (general for installer) WrtErrStatus error code (wrt_type.h),
-    WrtErrStatus is used into installation callbacks and decides about information for user,

Any other error handling (in installer code) should be removed after all.

[Verification] Build repository

Change-Id: Id0b94f3c1f98f30e8dbbc80f2046a83272cb2d43