Add new errmsg length constant to ccpp_kinds

[peverwhee]

Description

In CAMDEN, we are currently using a parameter set to 512 to set the length of errmsg. We'd like to avoid having these parallel values of 512 (our parameter and the hard-coded error message length in the framework).

Solution

Add a CCPP-specific errmsg length to ccpp_kinds that could be used by host models and schemes.

Alternatives (optional)

In prebuild, error message length is set by the errmsg variable in the ccpp_t DDT in ccpp_types.F90. Since capgen doesn't use this module, we'd prefer to add the new error message length to ccpp_kinds

Related to (optional)

See discussion here (though it's summarized above): ESCOMP/CAM-SIMA#216