Support API version-specific RPC marshalling.
Replace get_syntax method of IPASimpleObject with new get_type method.

get_type returns the Python type for an LDAP attribute.
Use raw attribute values in command result when --raw is specified.

For backward compatibility, the values are converted to unicode, unless the
attribute is binary or the conversion fails.
Keep original name when setting attribute in LDAPEntry.
ipalib: Add DateTime parameter

Adds a parameter that represents a DateTime format using datetime.datetime
object from python's native datetime library.

In the CLI, accepts one of the following formats:
    Accepts LDAP Generalized time without in the following format:
       '%Y%m%d%H%M%SZ'

    Accepts subset of values defined by ISO 8601:
        '%Y-%m-%dT%H:%M:%SZ'
        '%Y-%m-%dT%H:%MZ'
        '%Y-%m-%dZ'

    Also accepts above formats using ' ' (space) as a separator instead of 'T'.

As a simplification, it does not deal with timezone info and ISO 8601
values with timezone info (+-hhmm) are rejected. Values are expected
to be in the UTC timezone.

Values are saved to LDAP as LDAP Generalized time values in the format
'%Y%m%d%H%SZ' (no time fractions and UTC timezone is assumed). To avoid
confusion, in addition to subset of ISO 8601 values, the LDAP generalized
time in the format '%Y%m%d%H%M%SZ' is also accepted as an input (as this is the
format user will see on the output).

Part of: https://fedorahosted.org/freeipa/ticket/3306
ipalib: Expose krbPrincipalExpiration in CLI

Adds a krbPrincipalExpiration attribute to the user class
in user.py ipalib plugin as a DateTime parameter.

Part of: https://fedorahosted.org/freeipa/ticket/3306