Merge pull request #1006 in SNORT/snort3 from smb_unicode_fname to master

Merge pull request #1006 in SNORT/snort3 from smb_unicode_fname to master

Squashed commit of the following:

commit aec151308a6b538db68baddeec1a09b956849993
Author: snorty <mdagon@cisco.com>
Date:   Wed Sep 20 17:40:48 2017 -0400

    Missed 2 files

commit 31c622a7fba16becbf5f6b24ce490e4a36cecb78
Author: snorty <mdagon@cisco.com>
Date:   Tue Sep 19 15:19:46 2017 -0400

    Additional changes from Michael's branch - cmake changes for iconv + additional improvements

commit 3758b4d8604c1b1fafce1138942b8f8f20c58ec3
Author: Michael Altizer <mialtize@cisco.com>
Date:   Fri Sep 15 14:47:57 2017 -0400

    build: Import iconv autotools logic from gnulib

commit ef23d1dabc7326091010988a6e0aa0cb936bcc5f
Author: mdagon <mdagon@cisco.com>
Date:   Mon Jul 24 10:29:15 2017 -0400

    SMB unicode filename support

    1. iconv is used for translating UTF16-LE file names to UTF8.
    2. Smb will add BOM to file name in case it is Unicode.
    3. Translation will be done in file_api during logging.
    4. Active response was updated to keep the same format of the original file name.
    5. File api was updated to use pipe-delimited hex for file names:
       printable text will show up as plain text and any 8-bit chars as hex
    6. Full file name, including path, will be logged, instead of only the file name
    7. NHI will send raw uri instead of normalized uri to file api