Function names differing only by trailing underscore

[jphickey]

CF has a number of cases where function names differ only in a trailing underscore(s), which is likely to violate some coding standards because they look too similar and can be easily confused. An example offender is CF_CFDP_TxFile(), CF_CFDP_TxFile_(), and CF_CFDP_TxFile__().

These internal helpers with only trailing underscores should be renamed to something more descriptive to make it clear what the intent of the function really is (e.g. in the example, the double-underscore version seems to be simply a wrapper to initialize the transaction structure ... seems to have nothing to do with sending files at all, really - just a generic initialization helper).

[jphickey]

This was originally noted in #42 but split to a separate work item

[jphickey]

After PR #137 (which fixes a few) the following name issues remain:

CF_CFDP_CycleTx_
CF_CFDP_TxFile_
CF_CFDP_PlaybackDir_
CF_DoSuspRes_
CF_CmdCancel_
CF_CmdAbandon_
CF_FindTransactionBySequenceNumber_
CF_TraverseAllTransactions_